Plants – Discover-Nature

American Asters

As we enter early autumn, it is late in the growing season for the central United States, and many insect species are still actively looking for pollen and nectar as they get ready for winter. Migrating birds and species that overwinter here are also seeking daily meals. Fall flowering plant species are much fewer in number than summer blooming species, but include varieties of American asters, Symphyotrichum spp.; goldenrod, Solidago spp.; black-eyed Susans, Rudbeckia spp.; coneflower, Echinacea spp.; sedum, Sedum spp.; and anise hyssop, Agastache spp.

^{American Aster by Andrew McKinlay, Aug 2013; Anise hyssop by Steve Guttman, Oct 2011; Black-eyed Susan by Jodi Grundig, Aug 2009; Coneflower by Bonnie Leer, Jul 2008; Goldenrod by Cathy Baird, Aug 2013; Sedum by Eleanor Martin, Jul 2009}

In this blog, we take a look at American asters, which make up a genus of over 100 species of perennial plants, all of which are native to North America. Asters like full or partial sun and reach heights of between one and six feet. They display a variety of colors from white to blue to purple. They do best in wet soils. Asters are often grown in pots or used in borders, as well as being found in a variety of wild habitats including forests, savannas, prairies, and wetlands.

^{American painted lady on Pacific aster by TJ Gehling, Oct 2023; Gulf fritillary on white aster by Vicki DeLoach, Ot 2012; Leaf cutter bee, Megachile spp, on New England aster, by GreenRavenPhotography, Sep 2016; Metallic green bee on white aster by Jacqui Trump, Oct 2021; Pecks skipper, Polites peckius, on smooth blue aster, Symphyotrichum laeve, by Tom Potterfield, Sep 2016}

These asters are an excellent source of nectar and pollen sought by both long-tongued and short-tongued bees, butterflies, wasps, and beetles. All parts of the plant are edible, although some species may contain mild toxins, making the animal eating it ill. Leaves and stems are eaten by grouse, turkey, chipmunks, mice, and deer. The abundant seeds are available long after most other flower seeds have been consumed or buried. Large quantities of seeds are eaten by migrating bird species including dark-eyed junco, Junco hyemalis; indigo bunting, Passerina cyanea; American tree sparrow, Spizelloides arborea; and American goldfinch, Spinus tristis.

^{American goldfinch, Spinus tristis, by F Delventhal, Jul 2022; American tree sparrow, Spizelloides arborea, by Tom Benson, Nov 2018; Dark-eyed junco, Junco hyemalis, by Stan Lupo, Mat 2020; Indigo bunting, Passerina cyanea, by Mitchell McConnell, Apr 2013}

Asters are sometimes referred to as a keystone species. Keystone species can be either plants or animals that are essential to maintaining the health and functions of the entire ecosystem to which they belong. The introduction or loss of a keystone species may significantly affect an entire ecosystem in either positive or negative ways. Populations of other organisms may be altered, habitat changes can be observed, and biodiversity can rapidly change. American asters, along with the other late blooming flower species, are an important food source late in the growing season for maintaining a healthy population of pollinators, migrating birds, and over-wintering wildlife.

To learn more about seasonal changes and how our native species are adapted to handle these conditions, consider a visit to the Jurica-Suchy Nature Museum or a nature center near you.

Greene Valley Trail

As the heat abated a little bit, we decided to take a hike at the DuPage County Greene Valley Forest Preserve in Naperville, Illinois, this past weekend. On the east side, in the central part of the preserve, a 2.25 mile trail loops from the south parking lot to the Southern DuPage County Regional Trail and the Valley Trail. Trails are well-marked, wide limestone paths, with plenty of room for walkers and bicycles.

We found a pleasant, open vista that was great for birdwatchers and prairie enthusiasts alike. The Valley Trail runs alongside the east branch of the DuPage River, which makes it attractive to bird species, although there is no view of the river for hikers. While it was an overcast day making bird identification difficult, we were able to observe those seen below:

^{Birds pictured above in clockwise order: Northern cardinal, Cardinalis cardinalis, by Mshake, Getty Images; Red-winged blackbird, Agelaius phoeniceus, by Robert Jakubowski, Pexels; Song sparrow, Melospiza melodia, by BrianEKushner, Getty Images; Common yellowthroat, Geothlypis trichas, by BrianEKushner, Getty Images; Field sparrow, Spizella pusilla, by Mr Jamsey, Getty Images Signature; Gray catbird, Dumetella carolinensis, by SKHoward, Getty Images Signature}

Vegetation varies greatly, providing good protection for many of the small mammals plus lots of perches for birds. Many plant varieties could be seen and identified without leaving the trails, including those pictured below.

Black raspberry, Rubus occidentalis; Edible in season
Climbing prairie rose, Rosa setigera; Pollinator species for bees
Common milkweed, Asclepias syriaca; Pollinator species supporting more than 450 species of insects
Cup plant, Silphium perfoliatum; Leaf wraps around the stem forming a water holding cup
Eastern Black Walnut, Juglans nigra; It is allelopathic, releasing chemicals from its roots that may give the tree some advantage over its nearest competitors for food and nutrients
Elderberry, Sambucus sp.; Sambucus is Greek for an ancient wind instrument sounding as a whistle
Grey headed coneflower, Ratibida pinnata; Perennial attractive to Butterflies & birds
Hemp dogbane, Apocynum cannabinum; All parts of the plant are toxic, possibly fatal
Joe Pye weed, Eutrochium sp; Considered medicinal by early American cultures
Northern red oak, Quercus rubra; Acorns need a minimum 3-month exposure to near freezing temperatures to germinate
Sumac, Rhus sp.; Prized as a spice from the cashew & mango tree families
Virginia creeper, Parthenocissus quinquefolia; Flowering vine in the grape family
Grey poplar, Populus x canescens; Cross between white poplar and Aspen
Wild bergamot, Monarda fistulosa; Considered medicinal in use as a tea for colds

^{Scroll through pictures above using the left & right arrows}

The area supported plenty of small mammals such as rabbit, shrew, deer, coyote, and both gray and fox squirrels. We saw lots of pollinators including bees, moths, butterflies, and dragonflies. Greene Valley Forest Preserve offers a wide range of hiking trails, a scenic overlook, camping and picnicking facilities, a model airplane field, and many events, including night sky observations throughout the year. Consider catching some of the amazing sights in natural areas near you.

^{Fauna pictured above in clockwise order: Coyote, Canis latrans, by Esteban Arango, pexels; Galls on grape leaves; White-tailed deer, Odocoileus virginianus, by Stefonlinton, Getty Images Signature; White cabbage butterfly, Pieris rapae, by Bejan Adrian, Pexels; Shrew by CreativeNature_nl, Getty Images; Eastern cottontail, Sylvilagus floridanus, by Brian Forsyth, Pexels}

Natives In Bloom

Spring has arrived in northern Illinois with warming temperatures and spring rains. At this time of year, we can observe many of the early ephemerals in bloom. Many of these species only bloom for a short period before the flowers are gone, but the plants continue to grow and put forth fruits and seeds before dying back altogether until next spring. Let’s take a look at what is blooming right now in our area.

^{Bloodroot, Sanguinaria canadensis, by DonArnold, 2025}

^{Bloodroot, Sanguinaria canadensis, colony by DonArnold, 2025}

Bloodroot, Sanguinaria canadensis, is one of the earliest plants to bloom as soon as warmer temperatures stabilize. It is a perennial that grows up to a foot tall. Each leaf unfolds to reveal a single white flower with bright yellow anthers. Each flower blooms for only one to two days, and the entire colony of plants last about two weeks.

^{Sharp-lobed hepatica, Hepatica nobilis acuta, by DonArnold, 2025}

Sharp-lobed hepatica, Hepatica nobilis acuta, a member of the buttercup family, reaches only a few inches in height. Flowers are white, pink, or blue, clustered in tufts of several blooms. They like woodlands and rocky bluffs, and flowers persist for two to three weeks.

^{Celandine poppy, Stylophorum diphyllum, by DonArnold, 2025}

Celandine poppy, Stylophorum diphyllum, is a taller plant between 12″ and 18″ in height. Each stem bursts forth in two to four golden yellow flowers. If cut open, the sap is an orangish-yellow color. After about three weeks, flowers die back and an inch long, ovoid seed capsule grows for several weeks before releasing numerous seeds upon splitting open.

^{Virginia bluebells, Mertensia virginica, by DonArnold, 2021}

Virginia bluebells, Mertensia virginica, stands tall at one to two feet. Pale pink or blue flower buds open to light blue tubular flowers. Blooms last about three weeks and make a dazzling display when plants are observed clustered over a large space in many shaded woodlands throughout the area.

^{Shooting Star, Dodecatheon meadia, by DonArnold, 2025}

Shooting star, Dodecatheon meadia, is a group of 17 subspecies of flowering plants found throughout North America and Siberia. Standing up to 18″ tall, a cluster of eight to twenty purple, pink, or white flowers with yellow stamens hang from the top of each stalk.

^{Spring Beauty, Claytonia virginica, by DonArnold, 2021}

Spring beauty flowers, Claytonia virginica, open on warm, sunny days but remain closed when clouds or cool breezes are present. They bloom for one to two months in late spring and like dappled sunlit areas. White blooms with pink lining give off a pleasant floral scent.

^{White trout lily, Erythronium albidum by DonArnold, 2021}

^{White Trout Lily bloom, Erythronium albidum, by DonArnold, 2021}

White trout lily, Erythronium albidum, grows in large patches of four to six inch high plants with bright white blooms that stand out among dark green leaves mottled with brown markings. The flower nods from a short stalk and blooms for about two weeks in late spring.

^{Cutleaf toothwort, Cardamine concatenata, by DonArnold, 2021}

Cutleaf toothwort, Cardamine concatenata, stands about ten inches tall with large-lobed, toothed leaves. Many small white flowers with yellow anthers bloom above the leaves for about two weeks.

^{Mayapple, Podophyllum peltatum, by DonArnold, 2021}

Mayapple, Podophyllum peltatum, stands up to eighteen inches tall. Infertile plants produce one leaf on a single stalk. Fertile plants have two leaves on petioles branching from the stalk, with a nodding flower growing from the juncture of the petioles. Flowers are pale white with a yellow or greenish middle.

^{Prairie trillium, Trillium recurvatum recurvatum, by Karly Tuminello}

^{Large-flowered trillium, Trillium grandiflorum, by СССР, May 2019}

Trillium grows in prairie and woodland habitats. There are seven recognized species, and two of the ones that you are most likely to observe in our area are large-flowered trillium, Trillium grandiflorum, and prairie trillium, Trillium recurvatum recurvatum. Large-flowered trillium is declining in population, preferring swamps or wet soil areas, which are also declining as development expands and destroys these habitats. Prairie trillium prefers open woodlands dominated by oak, hickory, and maple species. All species of trillium are notable for their structure consisting of three leaves and flowers with three petals.

^{Dutchmans Breeches, Dicentra cucullaria, by DonArnold, 2025}

^{Dutchmans Breeches, Dicentra cucullaria, by DonArnold, 2021}

Dutchman’s breeches, Dicentra cucullaria, stands about six inches tall, with a white flower shaped like a pair of pants hung upside-down from a pedicel. These plants are found in undisturbed woodlands, especially along ledges and ravines throughout Illinois.

^{Eastern redbud, Cercis canadensis, by Greg Hume, Apr 2005}

^{Eastern redbud, Cercis canadensis, buds up close by Greg Hume, Apr 2005}

Eastern redbud, Cercis canadensis, is a small tree or large shrub, growing up to thirty feet high. The bark is dark and smooth, and twigs are slender with a zig-zag appearance. Flowers bloom in mid to late spring and form small, vivid rose-colored bunches.

^{Serviceberry, Amalanchier sp, by DonArnold, 2025}

Amalanchier is a genus that includes about two dozen varieties of small trees or shrubs. These are known by several different common names including shadwood, serviceberry, sugarplum, saskatoon, and others. They bloom for short periods in late spring, displaying clusters of four to twenty white flowers. Small red berries grow in mid to late summer, but do not last long since they are a favorite food source for both birds and small mammals.

Getting out for a walk to your favorite prairie or woodland habitat over the next few weeks will provide the opportunity to observe many of these plants while they are in bloom, including our own woodland trail around Lake Benedictine here at the Jurica-Suchy Nature Museum.

Autumn Foods

Meteorological fall began September 1st, marking the beginning of cooling temperatures that lead into winter, the coldest time of the year in the northern hemisphere. As the days begin to cool, many plant species are producing ripe fruits and seeds and starting the process of going dormant until next spring’s warming temperatures and longer days signal a beginning of the next growing cycle. Some animals, especially birds, travel long distances, migrating to areas that stay warm throughout the year. Those who stay through the coldest months depend on having food sources available even while plants are dormant.

_{Grey-headed coneflower seed head by Laura Fischer Photography}

The best winter food sources for wildlife are native plants with berries and seeds available throughout the colder months. Birds including woodpeckers, robins, waxwings, bluebirds, thrushes, chickadees, quail, and thrashers rely on robust insect populations in summer. In winter, when insects are no longer available, having another food source such as seed heads and berries left standing in your garden fulfills this need while adding visual interest and wildlife watching opportunities for you.

^{Food items shown above: Acorns on forest floor by Liz West, Oct 2006; Shellbark hickory nuts by HeikeRau, Getty Images; Pine cones with seeds by GordonImages, Getty Images}

Several tree families including pine, hickory, oak, and cherry offer fruit and nuts lasting through the winter. Along with grass and wildflower stems, trunks and branches also provide habitat for insect eggs and larva that will emerge in the spring. Over winter, insects in these stages are available as food for foraging species that use beaks and claws to dig them out. Stems growing close together provide additional benefits as thickets that provide protection against cold winds and harsh weather and hiding places that are safe from other predators.

^{Berries & Seeds above: Aster seeds by David Hansche, Getty Images; Sunflower at sunset by Hazal Ak, Getty Images; Wild elderberries by StargateChris, Getty Images; Thistle seeds by JTCanada, Getty Images}

Sunflowers, elderberries, and serviceberries are important food sources for fall migrators and winter inhabitants, providing fat and energy to stay warm and active. Aster, thistle, and conifer seeds released throughout the colder months are a favorite food source for finches and other small perching birds. Oak acorns, beechnuts, and hickory nuts are eaten by many woodland animals including squirrel, chipmunk, deer, wild turkey, fox, and quail.

^{Wildlife enjoying an offering: Blue tit on suet by Hedera.Baltica, Dec 2022; Lunch by Audrey, Feb 2008; Pine siskins on thistle by Yooperann, May 2015; Purple finches by Stan Lupo, Oct 2016}

Some of these animals also forage through our backyards in winter as many berry producing plants in the wild are stripped bare during late autumn and early winter. Backyard plantings and feeders provide important supplementary food sources for these animals. A variety of species to consider planting include American persimmon, blackberry, blueberry, elderberry, raspberry, cranberry, paw-paw , and prickly pear cactus, holly, sumac, hackberry, viburnum, hawthorn, bayberry, red cedar, and juniper. You can learn more under Garden For Wildlife on the National Wildlife Federation website at https://www.nwf.org/Garden-for-Wildlife/Food.

Nature journaling is a great way to track your observations and learn more through later research

Opportunities to observe wildlife in your own backyard can be an exciting way to learn. Try tracking which plants are being eaten and at what times during the changing seasons. Record the weather conditions during those periods to learn what foods are relied upon during colder, harsher winter weather. Try a variety of suet, seed and nut varieties in feeders to attract a range of animals to your backyard for fun wildlife watching and education.

Oak Tree Habitat, pt.3

In the past couple of blogs, we learned that oak trees are a keystone species in their habitat, especially for the vast network of relationships between oaks and insects.

^{Ladybug on oak tree leaf by EMFA16, Getty Images}

^{Leaf litter and under-bark room for rent, by Wayne S. Grazio, Nov 2013}

^{Insect holes & homes on cork oak, Quercus suber, by Bloor4ik, Getty Images}

Oak trees and their surroundings provide shelter and food from leaves, wood, bark, sap, flowers, pollen, and acorns to thousands of species of insects and other invertebrates. Shelter is provided on the tree, inside cavities or other fissures, among the leaf litter, and around the root systems. As oaks age, there are more opportunities for shelter and food, including after branches or the whole tree dies and falls to decay on the forest floor.

^{Chickadee nest by Jack VandenHeuval, Getty Images}

^{Chickadee eating a caterpillar by Bettina Arrigoni, May 2018}

Over 900 caterpillar species have been identified in oak habitats, more than three times the number found in forests dominated by maple trees. Canopy leaves and branches provide shelter and nesting opportunities for dozens of bird species who find a ready source of food within the insect populations. Ninety percent of bird species feed insects, especially caterpillars, to their young. The Carolina Chickadee feeds four to six chicks for 16 days before they fledge. Mealtimes require 400 to 500 caterpillars each day.

^{Aphids and ants by oday222, Getty Images Pro}

^{Philodromus praedatus spiders live mainly in mature oak trees, by Nikk, May 2016}

^{Oak gall by Michael Boubin, Getty Images}

Several species of flies and wasps lay their eggs on oak trees, stimulating a growth hormone in the tree to grow a gall, an outgrowth of bark, around the eggs. When the larvae hatch, secretions from the gall feed the larvae, and the gall provides protection to the developing insects. The abundance of insects attracts other invertebrates from higher up on the food chain. Spiders frequently inhabit mature oak trees hunting and feeding on many of the insect species. Aphid colonies are often found on oak trees, but cause little damage to the tree. Aphids feed on the sap from the tree and secrete a sticky, sugary substance called honeydew, a favorite food for ants. The ants protect the aphid colonies, keeping them underground during inclement weather and herding them up the tree in summer to ensure the aphids are well fed to keep producing more honeydew.

^{Fall webworm, Hyphantria cunea, by Anita Gould, Sep 2015; Polyphemus moth caterpillar, Antheraea polyphemus, by Ed Uthman, Sec 2018; Speckled wood caterpillar, Pararge aegeria, by Dean Morley, May 2013; Linden looper caterpillar, Erannis tillaria, by sankax, Jun 2009}

Insects and oak trees have created an environment rich in food for many of its inhabitants. According to Doug Tallamy, a leading entomologist at the University of Delaware, “caterpillars transfer more energy from plants to other animals than any other type of creature.” The loss of habitat for insects puts considerable strain on all other environments, including ones supporting ourselves. Insects do most of the work of pollination, allowing plants to reproduce. They also provide for quick decomposition and the return of nutrients to the soil for growing new plants. Insects are a driving force of the world’s food webs and are necessary for a healthy environment.

There are over 400 species of oaks worldwide, with about one quarter found in North America. As we have briefly touched upon in this series of blogs, oak trees provide opportunities for healthy habitats for many other species. For information and further discussion on the relationships between caterpillars and oak trees, please see The Nature Of Oaks, by Doug Tallamy.

Oak Tree Habitat, pt.2

In the last blog, we discussed oak trees as a keystone species, substantially affecting the types and abundance of other species in their habitat. There are 400-500 species of oaks worldwide, supporting an extraordinary 2,300 wildlife species not including fungi, bacteria, and other microorganisms. Oak trees in all stages of life and death have numerous biotic relationships with wildlife.

^{Badger in tree cavity by Byrdyak, Getty Images||Golden millipede in Lagos by efeghali, Getty Images||Neanura springtail by Henrik_L, Getty Images||Pileated woodpecker in oak tree by mtruchon, Getty Images||Slug & rollie pollies by Sonya Kate Wilson, Getty Images||Wood Mouse in tree cavity by byjohn, Getty Images}

Fungi are often identified as attacking oak trees, but they can have very beneficial relationships. Fungi growing in the ground assist an oak tree in getting nitrogen, phosphorous, and other nutrients out of the soil, and in return get carbon and energy from the sugars in the tree’s sap. Oaks provide a place to live for over 700 species of lichens, plus uncounted liverworts and mosses. Lichens covering the oak’s surface help to keep them free of fungal infections and invasive insects. Liverworts and mosses help oaks to retain water and release it into the soil over a long period of time. As oak limbs fall and decay, water retention softens the wood providing food and habitat for decomposers.

Green moss on oak tree by tntemerson, Getty Images

Lichen & peat moss on oak by Sean Gardner, Getty Images

Fallen oak leaves are slow to decompose due to their tannin and lignin content, both preservative compounds. Leaf litter, composed of several layers of fallen leaves, becomes habitat for many millions of species including millipedes, springtails, woodlice, slugs, beetles, ants, and other organisms that feed on decaying plants. Through their activities, the creatures of the leaf litter help to return nutrients to the trees.

Oak forest leaf litter by Tina_C_Olsen, Getty Images

Acorns, with high amounts of fats, proteins, and carbohydrates, are one of the healthiest and most sought after foods in the woodland. White oaks, living between 200 and 300 years, will produce about 3 million acorns during their lifetime. Many bird species eat acorns, but oak trees enjoy a special relationship with blue jays, whose beaks are strong enough to pry an acorn open. In autumn, blue jays enjoy feeding on acorns, but also cache them for winter, burying several at a time under a few inches of soil in various locations up to a mile from the originating tree. Although blue jays cache large quantities of acorns, they can only remember and retrieve about 25% of them, allowing many new oak trees to grow and spread into new areas.

Blue jay with red oak acorn by mirceaux, Getty Images

Oak trees support 31 mammal species who consume acorns for food, use the tree for shelter, or use the surrounding habitat for hunting. Gray squirrels and red squirrels favor acorns in the autumn and throughout the winter from caches hidden in nearby locations. They remember far more cache locations than blue jays, but there are still uneaten acorns that will germinate in spring to start new trees. Acorns are also a favorite food for badger, deer, wild board, and wood mouse.

^{Gray squirrel eating acorn by viktor2013, Getty Images}

^{Red squirrel with acorn by Neil_Burton, Getty Images}

Oak trees offer shelter for many species. Squirrels often build their nests high up among the leaves that provide protection from weather and predators. Dead branches, especially those with cavities, may remain on the tree for many years, providing excellent roost sites for bats. Open limbs, leafed areas, and cavities all provide nest sites for a variety of birds. In addition, the many insects drawn to oak trees provide a ready source of food for all of these nesters. Humans have been acorn consumers for millennia. Raw acorns, high in tannin content, can be toxic in larger quantities; but, properly prepared, acorns are high in calories, vitamin C, starch, magnesium, calcium, phosphorous, and antioxidants. They have been a food staple in many cultures and can be found in the records of ancient Greeks, Iberians, Japanese, and English.

Oak trees have many direct and indirect relationships with insects, which we will explore in the next blog.

Oak Tree Habitat, pt.1

Oak trees, genus Quercus, have over 400 species worldwide, but almost one-third are threatened with extinction. They are a keystone species, playing a central role in supporting the entire habitat in which they live. They maintain the structure and stability within their ecosystem, substantially affecting the types and abundance of other species. Oaks make up only 2% of plant species, but they directly support more than 30% of all plants and animals.

^{A great oak in Nottingham Forest by Peter Shaw, Getty Images}

Oak trees live from a few decades to several centuries. The Great Oak, Quercus agrifola, a species of Coast Live oak in California, is estimated to be over 2,000 years old. Oaks clean the air by absorbing pollution and sequestering carbon. They provide shelter, food, shade, and help to reduce erosion. Humans get food from the acorns, dyes from the tannin, and wood for construction, ships, and barrels, plus cork for stoppers and oak chips for smoking meat, fish, and cheese.

^{Red oak with new leaves, Quercus rubra, by aleroy4, Getty Images}

^{Oak forest leaf litter in winter by Whiteway, Getty Images Signature}

In spring, tender new leaves containing fresh sap are consumed by a variety of insects. In fall, older leaves will fall to the ground, but are slow to decompose, building up many layers of leaves over time which provide shelter for small woodland ground dwellers and food for decomposers.

^{Branches of red oak with catkins, Quercus rubra,}
^{by anmbph, Getty Images}

^{Texas Red Oak female flowers, Quercus buckleyi by Doug Goldman, USDA-NRCS National Plants Data Team}

Oak trees have both male and female flowers. Male flowers grow in early spring in long clusters hanging from tree limbs. The pollen is a favorite food for a large variety of insects, especially bees. Pollen is released slowly, over several weeks, to be blown by the wind to the female flowers, which appear as tiny, red flowers near the tips of twigs and new shoots. Female flowers are eaten by insects and are a favorite of red and gray squirrels. Oak flowers are one of the earliest food sources for animals in spring, and must be abundant on every tree so that some are able to survive to produce acorns, the seeds of the oak tree.

^{Bur Oak acorns, Quercus macrocarpa; Northern Red Oak acorns, Quercus rubra; Live Oak acorns, Quercus virginiana by Steve Hurst, ARS Systematic Botany and Mycology Laboratory, USDA-NRCS PLANTS Database;}

In late summer, after pollination, the female flower will produce a large, green nut called an acorn, which will mature in autumn, turn brown, and fall from the tree. Acorns are a nutritious food source for many animals, being high in energy, carbohydrates, and fat. In the eastern U.S., many species are dependent on acorn production, and the amount of available acorns significantly influences population sizes. Some acorns will find suitable ground for sending out a root and starting a new tree, but most will be eaten. Masting, an over-abundance of acorns, occurs every few years. It is thought that masting creates a better chance for new oak trees to grow by overwhelming the animal populations’ need for food. As a secondary result, animal populations may expand immediately following a mast year, only to have higher than normal mortality when food resources return to normal for the following years.

^{Bur Oak bark, Quercus macrocarpa by Herman, D.E., ND State Soil Conservation Committee, USDA-NRCS PLANTS Database}

^{Dead oak log in Bialowieza Forest by Nirian, Getty Images Signature}

Oak roots grow close to the ground’s surface and extend well beyond the circumference of the tree’s crown. A complex network of fungi live on the roots and provide additional nutrients to the tree, keeping both species healthy. As the trees grow and age, roots and bark develop crevices and holes in their surfaces, or chunks may become loose, providing niches for plants and animals to shelter and grow. Exposed wood gradually dies and decays providing even more habitat and food for decomposers and the other wildlife that live on them.

In our next post, we will take a look at some of the many species that oak trees directly and indirectly support with shelter, food, and breeding opportunities.

The Woodlands at the Turning, an Illinois oak savannah, by Justin Kern, Nov 4, 2013

Carnivorous Plants

Plants and insects have myriad relationships to one another. Some are mutually beneficial, as when plants offer nectar to feed insects which in turn pollinate the plants. Other relationships only benefit the insects when they feed on leaves, stems, and roots. For carnivorous plants, preying on insects to fulfill their need for nitrogen and other nutrients benefits only the plants.

^{Venus flytrap, Dionaea muscipula by Len Worthington, Aug, 2016}

Pitcher plants are carnivorous, living in bogs and fens found in warm weather areas. In North America, most species are found along the southeastern coastal states from Texas to West Virginia. Bogs are depressions filled with rain or melted snow, while fens are similar but get their water from surface or groundwater. Both types of wetlands are low in oxygen and nitrogen, very acidic, and often quite cold. These characteristics slow down the rate of decay in the vegetation of the wetland, further reducing the availability of nitrogen which is a vital component of chlorophyll, the compound used by plants, along with water, carbon dioxide, and energy, to photosynthesize sugar for food.

^{Tracy’s sundew, Drocera tracyi by Matthew Paulson, May 2022; Venus flytrap, Dionaea muscipula by Judy Gallagher, Jun 2022; White-topped pitcher plant, Sarracenia leucophylla, showing downward hairs by Aaron Carlson, Sep 2013}

Carnivorous plants use several strategies to attract and trap insects. Pitfall traps have slippery faced leaves forming a funnel with a pool of digestive enzymes waiting at the bottom. Downward facing hairs on the leaves make it harder for insects to climb out. Some plants use an opposite strategy and cover their leaf surfaces with a sticky secretion, trapping any insects that land on them. Still others have a leaf-like structure made of two halves that snap together when an insect lands on an inner surface, trapping the insect inside. In both of the last two instances, digestive enzymes are then released to cover, kill, and break down the insect body for absorption by the plant.

^{White-topped pitcher plant, Sarracenia leucophylla, traps separated from flowers by NC Orchid, Apr 2016}

^{Two-spotted bumblebee, Bombus bimaculatus by Judy Gallagher, Jun 2022}

Carnivorous plants are insect pollinated and must be able to attract pollinators without trapping them. All of the plant species go through a dormant period as seasonal temperatures get cooler. Traps die back and are regrown when warmer weather returns. In several species, flowers bloom and attract pollinators with nectar, completing fertilization before traps develop. Other plants separate the flowers and traps by a physical distance. Traps usually lie close to ground level to attract crawling insects, and flowers are grown on top of tall stalks to attract flying insects. A third method is to make the flowers less attractive to potential prey, and make the traps less attractive to potential pollinators. This is achieved by using different colors, patterns, and scents on flowers and traps.

^{Metallic green sweat bee, Agapostemon sericeus by Dann Thombs, Aug 2008}

^{Cobra lily, Darlingtonia californica by Charles Peterson, Mar 2018}

Whether you are growing these unique plants at home or viewing them in a botanical garden or out in the wild, some of the plants and their pollinators to watch for include the white-topped pitcher plant, Sarracenia leucophylla and the two-spotted bumblebee, Bombus bimaculatus; the cobra lily, Darlingtonia californica and the mining bee, Andrena nigrihirta, Tracy’s sundew, Drosera tracyi and the metallic green sweat bee, Agapostemon sericeus, and the Venus flytrap, Dionaea muscipula and any of the hoverfly species, Toxomerus sp.

^{Bog landscape by Chris Moody, Jun 2009}

Ash Trees

In the past, ash trees were one of the more common street trees in many urban areas of the United States. However, with the introduction of the Emerald ash borer, Agrilus planipennis, a member of the beetle family native to Asia, our native ash populations have suffered severe losses.

^{Emerald ash borer, Agrilus planipennis, by Leah Bauer, USDA FS Northern Research Station, Bugwood.org}

^{Emerald ash borer larva by Oregon Department of Agriculture, Mar 2023}

^{Emerald ash borer damage by John Hritz, Aug 2006}

Ash trees have been a popular “street tree” species for many urban areas. It is estimated that by the late 20th century, 20% of all parkway trees in Chicago were ash species. Green ash, Fraxinus pennsylvanica, likes moist soils, but grows well in most conditions. White ash, Fraxinus americana, is very similar to green ash, but prefers well-drained sites. Both have furrowed bark appearing as tight rectangular blocks on young trees, but deepening into longer furrows and ridges resembling a diamond-shaped pattern in mature trees. Black ash, Fraxinus nigra, often found on wet sites, is covered with irregular, knobby bumps. All the barks are grayish-brown.

^{Green ash, Fraxinus pennsylvanica, flowers by DonArnold, Aug 2023}

^{Ash tree samara by Herve Breton, Getty Images}

In spring, ash trees grow small green or purple flowers with no petals. Most are wind pollinated, although several bee species collect the pollen and contribute to some seed development. Flowers appear on both male and female trees, but only female trees develop seeds. Seeds are called samaras, or “helicopter seeds,” due to the distinctive whirling pattern they exhibit as they fall off the tree in a lazy spiral to the ground. The seed is housed in a fully rounded shell at one end of the single wing of each samara.

^{Green ash, pinnately compound leaves by Robert H. Mohlenbrock. 1989, USDA NRCS Wetland Science Institute (WSI), Lincoln}

Its pinnately compound leaves are another distinctive feature of the ash family. A compound leaf has a leaf blade divided into leaflets that are attached individually to the middle vein, each by its own stalk. The term pinnately refers to the arrangement of leaves, opposite one another along the middle vein. A terminal leaf, grown at the tip of the vein means there are always an odd number of leaflets, from 5 to 9 leaflets in ash species. Buds and branches also grow in this pattern, which can be observed on rose plants, as well as hickory and walnut trees.

^{White ash trees in autumn color by Cathy McCray, Nov 2016}

White ash is the main source of wood used in commercial applications. It is of medium weight and springy, able to absorb a shock and bounce back. This makes it valuable for bats, tennis rackets, bows and arrow shafts, along with a wide variety of other uses including tool handles, boats, and furniture. The seeds provide a valuable food source for several bird species including quail, duck, and turkey.

^{Green ash, Fraxinus pennsylvanica, bark by Kerry Woods, Apr 2022}

^{White ash, Fraxinus americana, bark by Virens, Sep 2009}

^{Black ash, Fraxinus nigra , bark by Robert H. Mohlenbrock, 1995, USDA NRCS Wetland Science Institute (WSI), Chester}

Although many, many ash trees have been lost to attacks from Emerald ash borers over the past couple decades, a small number of green ash have proven more resistant. They provide great shade for parks, yards, and large areas. In fall, watch as white ash trees turn beautiful shades of gold, deep purple, and maroon. Be sure to make note of them on your walks and check back in a few months to view their spectacular fall displays.

Buttonbush

Over the past several days, there has been a lot of activity in our backyard pollinator garden in the area surrounding the buttonbush, Cephalanthus occidentalis. This native shrub is a multi-stemmed flowering species that can grow from 3′ to more than 12′ tall. It needs lots of sunshine and prefers moist soils. Found in many habitats including sub-tropical swamps, shrub swamps in the northeast and upper Midwest, and southern and northern floodplain forests east of the Mississippi, this species prefers swampy backwater areas, marshes, wet meadow and bogs.

^{Buttonbush, Cephalanthus occidentalis, whorled leaves by loonyhiker, Oct 2010}

Newer stems are green, but quickly turn dark brown to almost black, becoming scaly with age. Leaves are opposite or whorled around the stem, each one protruding at a slightly different angle than the one above. It is thought that this arrangement provides maximum exposure of the plant’s total leaf surface to the sun.

^{Buttonbush flowers by DonArnold, Jul 2023}

^{Bumblebee on buttonbush by DonArnold, Jul 2023}

The flower clusters appear as small balls between 1/2″ and 1″ in diameter, with over 200 spikes poking outward covering their entire surface. Each spike is actually an individual flower. Flowers are closely grouped together and exude an intense, sweet fragrance. The plant reproduces through a two-stage cycle where pollen is produced and falls onto the immature pistil. As visiting insects brush through the closely grouped flowers, pollen rubs off onto their bodies. Once the pollen is gone, the pistil matures and becomes sticky at the end. As other insects arrive, pollen from other plants is picked up by the sticky end to pollinate the plant.

After pollination is complete, and the flowers drop off the plant, the ball-shaped seedhead turns completely brown. Unless it is brushed off by a passing animal or it is eaten, the seedhead may remain with the plant through the entire winter season, dropping off in spring. Seeds will often disperse into wetland areas, floating to shore. Each seed ball contains two nutlets.

^{Red Admiral butterfly on buttonbush by DonArnold, Jul 2023; Honney bee on buttonbush by DonArnold, Jul 2023; Long-tongued tiger swallowtail on buttonbush by Owen Sholes, Getty Images}

Pollinators include many long-tongued insect species especially bumblebees, honey bees, tiger swallowtail butterflies and black swallowtail butterflies. In addition, over two dozen bird species utilize the shrub for food, shelter, and nest building material – most notably are wood ducks that use the plant’s structure to shelter their young. Amphibians and reptiles hide among clusters of buttonbush in wetland areas for protection during the breeding season. Several honey-producing bee species are attracted to its pollen and nectar.

^{Buttonbush, Cephalanthus occidentalis, by NC Wetlands, Aug 2018}

With more than a dozen buttonbush species worldwide, it is an easy plant find and get close to for observing its flowers and fruits, as well as the behaviors of the many animal species that frequent this shrub.

Summer Berries

Across the northern hemisphere, as spring moves into summer, animals are able to find more food sources. Amelanchier and mulberry trees are two fruit-bearing plants that are favorites of many bird and mammal species, including humans.

^{Amelanchier trees by Leonora Enking, Apr 2010}

^{Mulberry flower by Sueviews, May 2006}

^{Amelanchier grandiflora flower by Kurt Stuber, 2004}

Amelanchier is a genus of 30 species of pome-bearing fruit trees in the family Rosacea. This family includes several other fruit-bearing trees including apples, pears, and plums. The tree is a favorite for landscapers with its many white flowers covering the tree in early spring and its brilliant hues of red and orange in the autumn. Amelanchier can be a single stem or a multi-stemmed plant and will grow in almost any soil type, but the ideal habitat is partly sunny, well-drained areas of open woodland.

Amelanchier are known by many names. Serviceberry comes from the fact that when the plants are in bloom, the ground is thawed enough to hold funeral services. In the Cree Indian language, it is known as saskatoon, a name still commonly used in western North America. Shadblow, in old English, refers to a time when the bloom indicated the shad were running. Juneberry refers to the time of year when the berries ripen.

^{Amelanchier fruit by Oregon State University, Jul 2013; Immature mulberry fruit by Geo Lightspeed7, Apr 2022; Unripe white mulberries by Petru Dimitriu}

Serviceberry fruit is slightly larger than a blueberry and tastes of blueberry, lightly peppered with strawberry and almonds. The berries are light green when young and gradually grow plump and sweet as they ripen to dark red and purple. They are a favorite of many bird species including robins and cedar waxwings in my area. Fruit is rapidly eaten as soon as it starts to darken, and almost none is left to fully ripen unless the tree is covered with netting.

^{Cardinal eating mulberry by Carolyn Lehrke, Jun 2015}

^{Robin and mulberries by Zone~V, Jan 2016}

Mulberry trees, of the genus Morus, have 64 species worldwide, and are another important summer food source. Red mulberry, Morus rubra, is the only one native to the United States. White mulberry, Morus alba, is native to South Asia but can be found on many continents, and it is considered an invasive in parts of Brazil and the U.S. All species grow quickly when they are young, reaching heights of nearly 80 feet.

Mulberry trees can be easily grown from either seed or a plant cutting. The market for their fruit is worldwide with some places, such as the U.S., importing millions of pounds each year. While easy to grow, establishing a viable crop for market has many difficulties. Trees do not produce fruit for the first ten years, and their highest yields are when the trees are 30-80 years old. The fruit is a favorite of many bird and mammal species, and is often eaten well before it is ripe enough to pick. Leading producers are Turkey and Iran who have been growing mulberries for several centuries.

^{Pick your own mulberry by Katarina, May 2014}

^{Mulberry cobbler by Eden, Janine and Jim, Jun 2021}

^{Mulberry jam by Amanda Slater, Jul 2021}

Plump, juicy, and sweet berries from both plants are high in vitamin C and iron. Fruits can be eaten straight from the trees or used in a variety of recipes. Other parts of these plants contain a milky sap that is mildly toxic to animals and humans if ingested. The wood is hard, tight-grained and heavy, with many of the same qualities as oak. It is used in furniture and fence posts. Historically, it has been used for arrow shafts and body armor. Amelanchier leaves and bark may be dangerous to cattle, sheep, and goats if consumed in large quantities. The white mulberry, Morus alba, is an important tree for the silk industry. The leaves of this species are the only food source for the silkworm, Bombyx mori; its cocoons are used to produce silk.

^{Silkworm, Bombyx mori, on Morus alba by Gorkaazk}

As you walk woodland areas near your home, watch for berry-loaded trees in your neighborhood. Keep track of each time you see them and what stage the berries are in – and how many are left on the tree. See if you can observe and learn more about who is eating this sweet, juicy food source of summer.

Ferns

Ferns are a group of well-known plants that first developed during the carboniferous period about 350 million years ago when the climate was stable, warm, and wet. Ferns were globally abundant in woodlands and marshlands providing suitable habitat for them.

Ferns were the first group of plants with vascular systems. Vascular plants utilize tube-like structures, called xylem tissue and phloem tissue. Water and minerals are moved from roots to fronds (leaves) through the xylem tissues and are used in photosynthesis to create food that is distributed throughout the rest of the plant in phloem tissues. Vascular systems also provide internal support so these plants can stand upright on their own.

^{Fertile fronds, Christmas fern in Sheipsit State Forest, CT by Holcy, Getty Images}

Early scientists noted that ferns came back every year, but produced no flowers or seeds. In 1669, it was discovered that spores grew on the surface of the fronds, but it was not until the mid-18th century that the entire reproductive process was understood. Spores are one-celled organisms that start to develop in springtime. They appear by the thousands as small green bumps on the undersides of fronds. As summer progresses, the sporangia, a capsule that contains the spore, turns brown. Clumps of these are called sori, and can easily be observed on fern fronds. In late summer, when the sporangia mature, they open and release their spores. Some plants will forcefully shoot their spores away from the fronds and some will open and let the spores drift away, caught by any small breeze.

^{Polystichum richardii in Stanley Park, Akaroa by Jon Sullivan, Aug 2006}

^{Lady fern sporangia by Kerry Woods, Mar 2013}

Most spores will not land in a spot with favorable growing conditions (fertile soil and water), but the spore may remain viable for up to a year, should conditions change. Spores do not contain a small plant like a seed does. A spore starts as a one-celled organism that grows by dividing itself in two during the first phase of reproduction called the gametophyte generation. As this division continues, a small structure called a prothallium grows, getting its nutrients directly from contact with water. Two more structures develop. The archegonium contains an egg, and the antheridium contains sperm. When water is present, the sperm will swim to the egg, fertilize it, and eventually a new, self-supporting plant grows.

^{Crozier shaped fronds by Ray Hems, Getty Images Signature}

The fern develops underground over the winter. In spring, when ground temperatures have risen, fernlets will push tightly coiled fiddleheads through the soil into the open air. A fiddlehead, also called a crozier, is a group of young, coiled fronds (leaves) of a fern. As the fern grows, the upper and lower surfaces of the fronds grow at different rates, and the fiddlehead uncoils, straightening out into several fronds. The plant is entering the second phase of reproduction, known as the sporophyte generation, where spores will be grown on the undersides of the fronds.

^{Green Boston fern frond, Nephrolepsis exaltata by Noppharat05081977 Getty Images}

^{Staghorn fern frond veins by IveehCoombs_Photography, Getty Images}

^{Staghorn ferns by Eyepark, Getty Images}

Ferns can also reproduce through cloning. The walking fern, Asplenium rhizophyllum, grows long fronds that eventually bend over and touch the ground. Wherever a tip touches moist soil, new roots are sent out, and a cloned plant develops. The Boston fern, Nephrolepsis exaltata, grows runners – leafless stems that branch out horizontally. Wherever they come in contact with moist soil, roots are sent out to clone another Boston fern. The staghorn fern, Platycerium sp, grows buds on its roots. As the soil around the plant is moistened by water containing nutrients, a new plant pushes upward through the soil from each bud.

^{Walking fern, Low Tatras mountains, Slovakia by Vrabelpeter1, Getty Images}

Ferns grow well in a variety of habitats. Many species prefer damp woodlands, but some grow on cliff faces or in rocky, dry locations. Be sure to watch for various species of ferns when you are out walking. A good field guide can help with fern identification and provide distinguishing information on this amazing plant group.

Maple Trees

Maple trees in the northern U.S. are coming into bloom at this time of year. Maples bloom in late winter and early spring, and the flowers come in green, yellow, orange, and red hues. There are about 130 species worldwide, and except for one species, all are found in the northern hemisphere across Asia, Europe, Africa, and North America. Thirteen maple trees are native to North America, and we will take a look at a few of the more common ones.

^{Holland Red Maple Swamp, Wisconsin State Natural Area by Joshua Mayer, May 2012}

Several species are large trees, reaching from 40′ to 65′ in height with 20″ to 60″ diameter trunks. Trunks are dark grayish-brown with ridged bark. Crowns appear generally rounded and root systems are widely spread. Maple trees do well in most habitats, particularly moist to wet soil, along streams or in bottomlands.

^{Sugar maple in spring by J Stephen Conn, Jul 2007}

Sugar maple, Acer saccharum, is well known for its maple syrup, marketed world-wide. When temperatures drop below 40˚, maple trees stop growing and excess starch is stored until temperatures start to rise again. Enzymes in the tree change the starch into sugar which is carried by tree sap flowing through the xylem and phloem cells, located just beneath the bark. A tap gently pounded through the bark intercepts some of the sap and collects it into buckets. It takes 40 gallons of sap to produce one gallon of maple syrup. Historically, the wood was used for railroad rails, plow blades, and wagon wheels. After burning, its ashes are rich in potash and make excellent fertilizer as well as an additive for soap and pottery glazing.

^{Maple tree tapping by PublicDomainPictures , Pixabay}

Black maple, Acer nigrum, is a close relative to the sugar maple, and these two species easily hybridize. Both species are shade tolerant, often found growing together for several years as understory trees. Sap from black maple trees may also be used in maple syrup production. Black and sugar maples are hardwoods, stronger and harder than other maple species, and valued for use as basketball court and bowling alley floors, workbenches, cutting boards, and baseball bats.

^{Bowling alley by vtwinpixel, Getty Images; Maple & other baseball bats by Comstock Images: Maple workbenches from thelinke, Getty Images Signature}

Red maple, Acer rubrum, provides food from seeds, buds, and flowers for squirrels, chipmunks, deer, moose, and elk. In winter, stumps and small twigs are an important food source for rabbits. Pollen is produced early in the spring and is a much needed food source at this time of year for bees and other pollinators. Red maple is also attractive to insects and fungi, which invade the wood and create many open cavities in trunks and large branches, favored as nesting sites for wood ducks and other species.

^{Red maple buds & flowers by Martin LaBar, March 2010}

^{Baby squirrel in maple tree by William Krumpelman, Getty Images}

Red maple has several qualities that have made it a widely used ornamental tree. It grows well in shady sites; it is tolerant of flooding and water-logged soils; it is one of the first to colonize disturbed sites and anchor the soil, and it has a rapid growth rate, colorful flowers and foliage, and lives 75 to 100 years. Maple flavored drinks, such as tea, are made from inner bark scrapings. Bark is also used in the production of ink and black or brown dyes. The wood is used for smoking meat and in the production of some whisky varieties.

Silver maple, Acer saccharinum, is a fast growing tree with a root system attracted to any source of water. It is easily grown in shady areas and wet soils, make it a well-liked ornamental tree. However, it causes many sewer and drain issues in urban settings in its search for water. The wood is hard but very brittle, and branches easily break in heavy winds. This often results in trunks having hollow cavities used for shelter by various animal species including wood ducks and squirrels. Seeds are abundant and are a favorite for birds and small mammals. The sap makes a delicious syrup, but requires twice as much volume as sugar maple trees, making it not commercially viable.

Box elder, Acer negundo, is another maple species that is often found near water. This tree easily tolerates drought and extreme cold, although the wood is weak compared to other maple species, and branches often break when subjected to heavy loads of snow and ice. Box elder produces abundant seeds late in the year that provide a great winter food source for mice, squirrels, and seed-eating birds. Branches are small in diameter, so it is not often used for lumber, but it has several uses as pulp wood for producing crates, boxes, and composite wood panels.

^{Under the spreading maple by Jo Zimny, Oct 2020}

As you are out walking in your area, be sure to look for the many species of maple trees that grow in yards and woodlands, often distinguished by bright flowers, abundant seeds, and lively green foliage. Also, be sure to take the chance to observe their spectacular fall foliage later in the year.

Duck Potato Salad

Walking around a freshwater marsh, we can observe dozens of plants and animals. Daily sunlight provides hours of energy, but it is only usable by the plants, which create their own food in a process called photosynthesis. Plants may be fully submerged, floating, or living above the water’s surface, but all are vital components of the food supply.

^{Marsh panorama by Beyond_Invisible, Getty Images}

Just as animals breathe, plants also need to exchange gases, taking in carbon dioxide and releasing oxygen. Plants living in a marsh, where they are fully or partially saturated with water, have developed several strategies for the gas exchange process. Spongy tissue is a universal adaptation of marsh plants. Both stems and leaves contain large airspaces surrounding food producing cells which are well distributed throughout the plant. Airspaces also keep the plants lightweight and enable stems, leaves and flowers to float on or reach above the water’s surface.

Floating wisps of green algae are primitive plants that have been on earth for over two billion years and are the basic food source for all life in the marsh. Millions of microscopic animals, crustaceans, insects, and small fish depend directly on green algae for their food. Green algae lack stems, leaves and flowers, but grow as long chains of nearly identical cells. Some algae are microscopic, some can be easily observed as green strands on or below the water’s surface and some grow to several hundred feet in length.

^{Duckweed forest pond by Sunsju, Aug 2019}

Duckweeds refer to a group of tiny, flowering plants that float on the surface of wetland areas. They reproduce by dividing their cells. This is a rapid process taking from 16 to 48 hours. In optimal growing conditions, with plenty of sunlight and nutrients available, the surface area of a pond can be covered in a very short period of time. Several species of pond plants grow long, narrow leaves with soft, nourishing cells providing a easy-to-eat and tasty treat for marsh dwellers. With large airspaces, these plants are able to stay afloat no matter how long they grow.

^{Spatterdock by Kirill Ignatyev, Jul 2011}

Plants with floating leaves, such as spatterdock, must have a method for preventing excess water from entering leaves and stems when they exchange gases. Plants have stomata, openings in the leaf where gases are exchanged. In terrestrial plants, stomata are located on the undersides of leaves to prevent rain from entering the opening. Floating leaves have stomata on the upper side of the leaf, providing far less exposure to water.

^{Water marigold by Gennady Alexandrov, May 2014}

Water marigold has two types of leaves, one that grows on the stem above the water’s surface and another that grows on the submerged stems. Leaves growing in air take in carbon dioxide and release oxygen through their stomata. Submerged leaves have very thin cell walls and exchange the same gases directly with the water surrounding them.

^{Arrowhead with bulb, -duck potato’, lower right, by Andriy Nekrasov, Getty Images}

Arrowhead is firmly anchored in the bottom of ponds, and has stems, leaves, and flowers growing above the surface. It reproduces by both seeds grown from pollinated flowers and bulbs grown on submerged stems. Bulbs remain submerged, attached to the stem and grow until they are mature enough to anchor themselves in the bottom silt and start another plant. While growing, the bulbs are very tasty and are a favorite food of many duck species, earning the nickname duck potatoes.

^{Wild celery, Vallisneria americana, by Schizoform, Jun 2022}

Wild celery produces both male and female flowers. Female flowers are attached to long stems that float on the water’s surface. Male flowers break off underwater and float to the surface unattached, where they are blown around until they meet a female flower, transferring pollen by contact. The pollinated flower coils downward back under the surface where the seeds develop and are released into the water to start a new plant wherever they land on the silt bottom.

Marsh plants come in many forms and each is well adapted to the unique conditions of the habitat in which they live.

Autumn Seed Collecting

As the growing season winds down, plants are producing millions of seeds. Some of these seeds are collected every year and used in a variety of ways.

Collected seeds can be spread into areas that are not covered through natural seed dispersion. Seeding can add diversity to a habitat to improve the quality of the area, or provide new habitat for rare and endangered plants. Seeds add new species into disturbed ecosystems and help to establish plant diversity to overcome invasive species. New plant species provide host food sources for insects and structure for building nests and other shelters.

Purple coneflower, Echinacea purpurea by DonArnold, Sep 2022

Wild colombine, Aquilegia canadensis by DonArnold, Sep 2022

The amount of seed collected depends on how much seed is available. General guidelines are to harvest no more than half of all seed, less if the plants are only found in small populations. To avoid adversely affecting existing habitat, seeds are collected from several locations across different days. Seeds are usually collected in sites that are geologically and climatologically similar or connected to the site where the seed is to be dispersed.

Cardinal flower, Lobelia cardenalis by DonArnold, Sep 2022

Seeds can be immediately sown by hand into a new or adjacent area, but many seeds are stored for later use. Seeds are dried on racks or in paper bags to prevent mold. If possible, the stems and leaves, known as chaff, are separated from the seeds. Large seeds encased in hard outer shells are broken open using a hammer mill.

Prairie dropseed, Sporobolus heterolepsis by DonArnold, Sep 2022

Seeds in nature are exposed to many environmental conditions that play a role in determining when they will germinate. Some seeds must be exposed to freezing, thawing, fire, moistness, or a combination of these factors in order to sprout. Legumes require scarification, making small cuts across the skin of the seed. Fall grasses can be stored in large quantities provided they are kept dry, whereas spring ephemerals with fleshy, moist fruits must not be allowed to dry out, and are stored in cool, moist conditions.

Butterfly wed, Asclepias tuberosa by DonArnold, Sep 2022

Green dragon, Arisaema dracontium by DonArnold, Sep 2022

Black-eyed Susan, Rudbeckia hirta by DonArnold, Sep 2022

Seeds are often prepared in mixed batches by habitat type such as dry, wet, savanna, woodland, and wetland. Seeds can be planted late in fall prior to the ground freezing, over winter on top of snow or frozen ground, or in spring after the first thaw. For seeds that require freezing, plant in early winter and let nature do the work. If a burn is likely in the area, consider dispersing the seed after the burn.

Grey-headed coneflower, Ratabida pinnata by DonArnold, Sep 2022

Smooth Solomon’s seal, Polygonatum biflorum by DonArnold, Sep 2022

Stewards in charge of seed collecting keep extensive records of all activities. This helps with the selection of desired seeds in the future. Information collected may include GPS locations of seed collection sites, dates and species picked, weight of seeds after processing, and the processing methods applied to each seed species. In addition, the species included in each seed mix and the date and location where each mix is planted can provide information for assessment in subsequent seasons.

The gallery below includes a sampling of the many seeds that are available at summer’s end including Big bluestem, Andropogon gerardii; Butterfly weed, Asclepias tuberosa; Black-eyed susan, Rudbeckia hirta; Buttonbush, Cephelanthus occidentalis; Common ironweed, Vernonia fasciculata; Common milkweed; Asclepias syriaca; Golden Alexanders, Zizia aurea; Green dragon, Arisaema dracontium; Grey headed coneflower, Ratibida pinnata; Jack-in-the-Pulpit, Arisaema triphyllum; Smooth Solomon’s seal, Polygonatum biflorum; Prairie dropseed, Sporobolus heterolepsis; Shooting star, Dodecatheon meadia; Purple coneflower, Echinacea purpurea; Wild colombine, Aquilegia canadensis.

Coneflowers

Purples, yellows, and pinks to brighten your garden

Coneflowers are one of the summer’s many showy spectacles in the garden. There are nine species native to the central and eastern United States, four of which can be found growing in the wild in our area. Additional hybrids, available for sale in local garden centers, have been developed for their appearance and variety of colors.

Purple coneflower, pale purple coneflower, yellow coneflower in backyard garden by DonArnold, 2022

Coneflowers are perennials, growing from two to four feet in height. Blooming from midsummer to the first frost, they like full sun and well-drained soils. They are drought tolerant and do particularly well in poor soil conditions provided they get a small amount of water every few days.

Purple coneflower, Echinacea purpurea by DonArnold, 2021

Purple coneflower, Echinacea purpurea, is rare in naturally occurring habitat in northeastern Illinois: yet it is one of the most popular species in backyard gardens. Pale purple coneflower, Echinacea pallida, is another favorite in backyard gardens and is commonly used in local prairie restorations.

Pale purple coneflower, Echinacea pallida, by DonArnold, 2021

Yellow coneflower, Ratibida pinnata, by DonArnold, 2021

Yellow coneflower, Ratibida pinnata, also called gray-headed coneflower, has flowers on slim, tall spikes that can be seen waving in any slight breeze. It is heavily used in prairie restorations due to its tendency to germinate the first year after seeds are planted. Rough coneflower, Rudbeckia grandiflora, is very rare and found only in a few patches in northeastern Illinois, all in DuPage County.

Purple coneflower, Echinacea purpurea disc and ray florets by DonArnold, 2021

Coneflowers have a composite flowerhead with 200-300 rose-colored florets surrounded by eight to twenty-one ray florets in colors ranging from dark purple to pale pink to yellow or white. Leaves are hairy with a rough texture. Coneflowers spread by self-seeding, dropping seeds within a few feet of each plant as they bend and sway in the wind. The mother plant is a perennial and will continue to return each year.

Several dozen species of butterflies, bees, wasps, beetles, and flies feed off the nectar. Soldier beetles appear late in the season, feeding on insect eggs and larvae deposited on the plants by other insects. Seeds are also a favorite food item for goldfinch, cardinal, and blue jay. Seed heads left through the winter will continue to feed the area birds until spring.

Black Swallowtail on Purple coneflower by DonArnold, 2022

Consider adding some coneflowers to your backyard gardens and watch for the butterflies and birds that will soon visit.

Succulents

Plants that save water!

Succulents are a group of plants able to store water in their leaves, stems, and roots. This group includes between 8,000 and 10,000 species across several plant families, equal to 3%-5% of all plant species. They are found on every continent except Antarctica.

Backyard succulent garden by DonArnold, 2022

Succulents are largely perennial species storing water for use in drought periods. They have features that limit the amount of water loss from evaporation. Most species have thick cuticles, the outer skin, and fewer stomata, the cells on the underside of leaves used for exchanging gases, including carbon dioxide and oxygen, with the outside environment. Many plants exchange gases during non-daylight hours only.

By storing water, succulents are able to survive in habitats with limited water availability, including habitats that receive only dew or mist versus measurable rainfall. Limited water availability may also refer to habitats where infrequent rainfall occurs with lengthy intervening dry periods.

Aloe vera crosscut leaf by Evelyn Chu, Dec 2010

Additional water-saving features include round versus flat leaves and stems exposing less surface area to the air and thus reducing water loss through evaporation. Plant surfaces may be waxy, hairy, or spiny creating micro-habitats to further reduce air movement across the surface. Plants are able to seal and heal wounds quickly. Roots are shallow allowing the plant to absorb minute amounts of moisture reaching the soil.

Hydrangea leaf, flat leaf structure with large surface area, by DonArnold, 2022

Plants retaining large amounts of water must have robust support to handle the extra weight. In smaller plants, additional fiber strengthens stems and leaves. In larger plants, such as trees and shrubs, stems contain thicker wood walls to maintain their upright stature. This provides additional protection against wind damage. In most species, if any part of the plant is broken off, fragments are capable of taking root and growing a new plant.

Since water temperature does not fluctuate as rapidly as air temperature, succulents are able to stay warmer due to the large amount of retained water. Succulents are still vulnerable to damage at very low freezing temperatures, but only over a prolonged period of several hours.

Succulents are often found in homes and backyard gardens and are well-liked because of their low maintenance and unusual appearance. Popular varieties that may come to mind include aloe vera, Christmas cactus, jade plant, sedum, and yucca. Consider starting a small pot on your windowsill or planting some in your backyard. Note: Be sure to pay close attention to the labels identifying which can be grown outdoors in your area.

Aloe vera by Forest & Kim Starr, Dec 2015

Jade plant, Crassula argentea by Hornbeam Arts, Nov 2012

Common Milkweed Pollinators

Observe dozens of pollinator species on one plant

Butterfly weed, Asclepias incarnata, with bee, genus Andrena, by DonArnold 2020

Swamp milkweed, Asclepias incarnata, and monarch butterfly, Danaus plexippus by NatureNerd 2015

There are 15 species of milkweeds in the Chicago area. The genus name, Asclepias is named after the physician Aesculapius, the son of Apollo, who studied medicine under Chiron, a centaur in Greek mythology of great wisdom and knowledge of medicine. The common milkweed, Asclepias syriaca is found in several different habitats that all have plenty of sun and disturbed soils. These areas include old fields, pastures, remnant prairies, fens and along roadsides and railroads. This species and several other milkweed species are favorite plants in backyard gardens.

Common milkweed, Asclepias syriaca by DonArnold 2022

Common milkweed supports many insects and pollinator species. All parts of the plant are used for food including nectar, pollen, foliage and stems. Several species also breed on common milkweed, laying eggs in flowers where larva can feed on nectar and later move to feed on foliage.

Common milkweed foliage, Asclepias syriaca, by DonArnold 2022

Nectar provides food for 14 species of butterflies, four beetles, one weevil, six plant bugs, eight ants, 41 bees, six wasps, and six flies. The bees, wasps and flies also eat the pollen as do an additional ten beetles, three weevils and two ant species.

Black Swallowtail Butterfly, Eastern Tiger Swallowtail Butterfly, Monarch Butterfly, bees in the Andrena genus, and Hummingbird Moths are some of the more common insects that you can observe on milkweeds.

Eastern black swallowtail, Papilio polyxenes, by DonArnold 2020

Monarch butterfly,Danaus plexippus, by DonArnold 2020

All of the bees, wasps, and flies mentioned above plus ten beetle species, three weevils, and two ant species gather pollen from the flowers.

Bee, genus Andrena, on common milkweed by DonArnold 2022

Hummingbird moth, Hemaris thysbe, by DonArnold 2022

Milkweed foliage is food for three beetle species, one earwig, one leaf miner, and one weevil. The foliage also supports seven species of aphids and their symbiotic partners, ten ant species. The aphids feed on the common milkweed stem and leaves, then produce a sweet substance that the ants use for food. In return, the ants provide protection from predators for the aphids.

Ants & aphids on milkweed stem by Linda Tanner, 2012

Observing the many species of insects using this one plant throughout the day is fun and interesting. Many other milkweed species and insect groups are also found in our area. Take along a camera or hand lens on your next walk and watch closely to see all of the activity!

Milkweed beetle on common milkweed by DonArnold 2022

Honey bee, beetle and bumble bee on common milkweed by DonArnold 2022

Long-legged fly on common milkweed by DonArnold 2022

A Spring Walk

The weather has included a lot of rain in these past few days, and there is more coming. Temperatures are still cool at night, but getting quite warm during the day, contributing to unstable air, thunderstorms, and tornado watches. Vegetation in our area is green and lush, inviting for the many species that inhabit our area. I hope you enjoy the sounds and pictures of spring and some of the inviting observations we can look forward to in the near future.

Boreal chorus frogs, Pseudacris maculata, are still out calling, even though it is near the end of their breeding season.

by DonArnold 2022

Another early spring species, white trout lily, Erythronium albidum, is still blooming.

by DonArnold 2010

And now that warmer weather is here to stay, both eastern garter snakes, Thamnophis sirtalis, and plains garter snakes, Thamnophis radix, are moving away from their winter dens and dispersing into woods and fields.

Garters emerging from winter den by DonArnold 2021

Golden Alexanders, Zizia aurea, and celandine poppy, Stylophorum diphyllum, are making a bright yellow welcoming splash for the next several weeks.

Weather always plays a large role in late spring in northern Illinois. A good thunderstorm can bring wonderful, soaking rains or wind and lightning to drive us indoors.

Thunderheads are a weekly happening by DonArnold 1986

Many species depend on water in ephemeral ponds at this time of year, including frogs, toads and salamanders. First to call are chorus frogs, Pseudacris maculata, then gray tree frogs, Hyla versicolor, and finally bullfrogs, Lithobates catesbeianus, call well into summer.

Gray tree frogs calling by DonArnold 2022

Bullfrog at Waterfall Place by DonArnold 2020

As spring moves into early summer, look for wood ducks, Aix sponsa, in woodland ponds

by DonArnold 2012

And mallards, Anas platyrhynchos, with puffball babies keeping close to mama

by DonArnold 2020

Green dragons, Arisaema dracontium, and their close relative, Jack-In-The-Pulpit, Arisaema triphyllum, are already standing tall

Other species to begin to watch for in the coming weeks include bumblebees gathering pollen from flora of all species and Eastern black swallowtail caterpillars, Papilio polyxenes asterius, destined to fly away at summer’s end.

Bumblebee collecting rose pollen by DonArnold 2020

Eastern Black Swallowtail larvae on fennel by SueOBrien 2020

I hope you are able to observe these and many other sights in the coming weeks on your neighborhood walk or in local forest preserves.

Mushrooms in the Woods

Springtime fungi fruit

Fungi, neither plants nor animals, have a kingdom of their own, and there are over 1,000 species in northern Illinois. Fungi have no roots, leaves, flowers, stems, nor chlorophyll. They do not make their own food, but obtain nutrients from decaying organic matter. Most are never seen, living underground or inside other species. For many fungi, when it is time to reproduce, they grow an aboveground fruit called a mushroom.

Eastern yellow fly agaric, Amanita muscaria, club-mushroom by Nicholas A. Tonelli, Sep 2011

Puffball, Calbovista subsculpta, by Alan Rockefeller, Jun 2009

Hymenophore, that produce spores, are located near the top of the mushroom. A spore is a small, usually single-celled, reproductive unit able to grow into a new fungi without sexual fusion with another individual. Spores can move about by wind, water, or insects. Mushrooms are classified into one of two groups depending on how spores are released. Club-fungi, basidiomycetes, drop their spores from the exterior surface of their club-like caps. Sac-fungi, ascomycetes, shoot their spores outward from inside a sac-like structure under the mushroom’s cap.

Yellow morel, Morchella esculenta, by Under the same moon, May 2011

Scarlet elf cup by Paul Boudreau, Apr 2018

Different types of fungi can be found in a forest ecosystem. Saprophytic fungi feed on dead organic matter, helping decomposition and returning nutrients to the soil. Mutualistic fungi work with a host plant to benefit both organisms. An example critical to many forest species in our area is the association of fungi and plant roots known as mycorrhizae. Plants provide food in the form of carbohydrates to the fungi. In return, fungi made of long slender tubes, looking like a spider’s web, attaches itself to the plant’s root system, increasing the root’s surface area and allowing more water and nutrients to be absorbed.

Mycorrhizae fungus wrapping tree roots by Univ of Pennsylvania, 1934

In addition to providing beneficial services to plants, fungi play an important role in maintaining healthy habitat for many area wildlife species. Tree cavities, created from decomposing wood in snags, are used for shelter by birds, small mammals, and insects. Rotting logs found on the forest floor offer food, shelter, and protection for salamanders and frogs. Carpenter ants build their nests by hollowing out a cavity in rotting wood.

Pileated woodpecker in tree cavity by Yeimaya, Mar 2006

Raccoon in tree cavity by Steve Burt, May 2010

Carpenter ants in decayed wood log by Bryant Olsen, Jun 2014

The largest living organism in the world is a fungus in Oregon, covering an area three-and-a-half miles in diameter and estimated to be 2,400 years old. In addition, at 6 million tons annually, mushrooms are the fifth largest crop in the United States. It is generally accepted that mushrooms are slowly disappearing as are forested areas, but none are listed as threatened nor endangered because so little is known about them. Consider taking along a mushroom field guide on your next woodland walk.

Mushrooms for sale by Chris Bertram, Feb 2007

Spring Wetland Vegetation

Early spring vegetation provides egg laying opportunities & protection

In early spring, when temperatures are still cool at night and daylight hours are just starting to lengthen, most plants are just starting to become active. Many amphibian and bird species also start their breeding activities at this time of year, and some of those depend on wetlands for egg laying sites, nesting material, food, and protection. Wetland vegetation creates important habitat for these species.

Emergent wetland at Kino Environmental Restoration project by Desert LCC, Aug 2018

Emergent plants are non-woody species that are rooted in wetland bottoms, but grow tall and emerge above the surface of the water. There are three categories of emergent plants that are important to pond life, including narrow-leaved emergents, broad-leaved emergents, and tall-robust emergents. Additional plants that affect wildlife populations in wetlands include floating plants, shrubs and trees.

Common bur reed, Sparganium eurycarpum, by USFWS Mountain-Prairie, Jul 2008

Common beggar’s ticks, Bidens frondosa, by Gertjan van Noord, Jul 2020

Marsh smartweed, Persicaria amphibia stipulacea, by Tom Wilberding, Aug 2020

Blue-joint grass, Calamagrostis canadensis, at Silver Lake, Utah, by Andrey Zharkikh, Aug 2014

Water willow, Justicia americana, by peganum, Jul 2017

Horsetail, Equisetum arvense, by delirium florens, May 2020

Narrow-leaved emergent plants are grasslike, with narrow stems and leaves, and grow to less than six feet in height. They come from the plant families that include sedges, Carex; rushes, Juncus; and bulrushes, Scripus. Some common narrow-leaved emergents of northern Illinois are common bur reed, Sparganium eurycarpum; horsetail, Equisetum arvense; reed canary grass, Phalaris arundinacea; and blue-joint grass, Calamagrostis canadensis. They provide cover for tadpoles and stems for perching birds to call from. Underwater stems are used to anchor frog egg sacs, and above surface leaves are used for egg laying by several species of dragonflies and damselflies.

Spot-tailed dasher, Micrathyria aequalis, on emergent vegetation by Allan Hopkins, Dec 2012

Eggs sacs anchored on emergent vegetation by JW112211, Apr 2006

Broad-leaved emergent plants are characterized by leaves almost as wide as they are long, and they grow to under three feet in height. Common species in northern Illinois include marsh smartweed, Persicaria amphibia stipulacea; common beggar’s ticks, Bidens frondosa; and water willow, Justicia americana. With broader leaves, these species provide excellent protection for adult and juvenile amphibians.

Cattail marsh at Jay Meiner Wetlands by Justin Meissen, Aug 2006

Tall-robust emergent plants are 5′ to 9′ tall when mature. Leaf and stem sizes vary greatly. In winter, some of the plants may die back or collapse, but many species grow in tightly packed stands where portions of the plant group will survive the entire winter. Examples in northern Illinois include narrow-leaved cattail, Typha angustifolia and broad-leaved cattail, Typha latifolia. In addition, common reed, Phragmites australis, is a highly invasive species found throughout our area.

Tadpole under duckweed by Helena, Jun 2007

Two other groups of plants are important to early spring wildlife. Shrubs, woody plants from 3′ to 9′ tall, and trees, woody plants over 9′ tall. Growing on wetland banks or in shallow water, trees and shrubs have branches and leaves that may be submerged or growing just above the surface. These provide perches for calling species, and some may be used for egg-laying sites. Common species in our area include blue-fruited dogwood, Cornus obliqua; silver maple, Acer saccharinum; and buttonbush, Cephelanthus occidentalis. Floating plants only grow on the surface where there is several inches of water. They are good indicators of water depth and the extent of open water in wetlands. They provide cover for many underwater eggs and juveniles. Duckweeds of the Lemna family and pond lilies in the Nuphar and Nymphaea families are common floating plants in this area.

Buttonbush, Cephelanthus occidentalis, by Jenny Evans, May 2008

Wetlands with emergent vegetation and stable water levels provide healthy habitat for bird, insect, and amphibian breeding populations. As you are out walking this spring, be sure to look at wetland vegetation and how it is used by the wildlife populations living there.

Early Spring Blooms

On wildflower or garden walks, be sure to look for these first-of-spring blooms.

White-throated snow drops, *Galanthus nivalis*, by Conall, Jan 2019

In these first weeks of spring, there are flowers that bloom only at this time of year. Most of these are out now, or will be out shortly, and they do not last very long. Some are native wildflowers found in woodland walks, and others are cultivated in gardens. But, all of these species bloom with warming temperatures and the rains of spring.

Doubke green spots on the inner petals are visible at the base and tip of each petal

Green-throated snow drops, Galanthus elwesii, by beautifulcataya, Mar 2010

Green-throated snow drops, also known as giant snow drops, Galanthus elwesii, is one of the earliest flowers, often blooming while there is still snow on the ground. It has a small flower with petals that are white on the outside and have double green spots on the inside. They begin blooming as early as mid-February.

Green extends the length of the inner petal.

White-throated snow drops, Galanthus nivalis, by Tico, Feb 2008

White-throated snow drops, or common snow drops, Galanthus nivalis, another springtime ephemeral, bloom about a month later. Flowers are similar with green extending the full length of the inner petal. When spring is warm and sunny, they are here for two to three weeks, but may last longer in cooler, rainy weather. Snow drops provide an important source of nectar and pollen for several bee species active early in the year.

Daffodils are all in the genus Narcissus. There are thousands of varieties all having dark green leaves with a single stem supporting a lone flower, or an umbel of up to 20 blossoms. Flowers are generally white or yellow, although orange and pink varieties have been cultivated. Plants are rich in several alkaloid compounds used in the production of galantamine, a drug for the treatment of Alzheimer’s Disease.

Spring crocus, *Crocus vernus*, by Sarah’s Yard, Mar 2011

Spring crocus, *Crocus vernus*, by christina.sanvito, Mar 2015

A favorite flower early in the year is the spring crocus, Crocus vernus. This cultivated species blooms for a few short weeks in early spring. Flowers only open when they are brightly lit, and remain closed at night and on rainy and overcast days. There are numerous varieties including purple, white, yellow, red, and orange, and combinations of these colors.

Skunk cabbage, *Symplocarpus foetidus*, by Richard A. Howard Photograph Collection, Smithsonian Institution

Skunk cabbage, *Symplocarpus foetidus*, by William C. Taylor, 1989, USDA NRCS

Skunk cabbage, Symplocarpus foetidus, is the earliest blooming native wildflower in northern Illinois and is found in wetlands including swamps, seeps, fens, and bogs. The dark green leaves are often stained black from Septoria spiculosa, a leaf spot fungus. The flower, a purplish-green spadix, grows from the ground to 6″ tall. Flowers and bruised foliage both emit an odor of decay, attracting flies to pollinate the plant. A compound fruit develops, with several sections, each containing a single seed. Fruits mature by late summer and are eaten, carried off, or fall to the ground, where they will rot to expose the seed.

Blue Cohosh, *Caulophyllum thalictroides*, by Doug McGrady, May 2016

Blue Cohosh, *Caulophyllum thalictroides*, by Doug McGrady, Apr 2016

Blue Cohosh, *Caulophyllum thalictroides*, by Joshua Mayer, Sep 2016

Another of our woodland natives, blue Cohosh, Caulophyllum thalictroides, is found in mesic woodlands. A perennial, the plant grows from one to three feet tall. After pollination, a blue, fleshy fruit develops. The fruit is toxic to humans, but favored by mice and woodland birds, who are the primary disseminators by eating and spreading the seed throughout the forest.

Squirrel corn, *Dicentra canadensis*, by Don McGrady, Apr 2013

Squirrel corn, Dicentra canadensis, is another ephemeral of mesic woodlands. Often mistaken for Dutchman’s breeches, the flowers are yellow and oblong rather than white and round. Leaves are dark green, small, and grow close to the ground, while an 8″-12″ tall stem grows up from the center ending in 3-10 hanging flowers. Each flower develops several seeds, and each seed has its own elaiosome, a sweet food treat. Ants will take the seeds back to their nests, eat the elaiosome and discard the seed. Plants go dormant after the forest canopy fills in.

As you are out walking in woodlands or your neighborhood, be sure not to miss these early and brilliant colors of spring.

Tree Buds

Serviceberry, *Amelanchier arborea*, DonArnold Feb 2022

Trees produce buds for the next year’s leaves, flowers and shoots. They are small and not easily noticed among the foliage of a fully leafed-out tree, which is why they are easiest to spot in winter. Buds develop in late summer, when a tree has lots of energy from the sun, but is no longer growing new leaves and branches as the tree prepares for winter.

Bur Oak, *Quercus macrocarpa*, by DonArnold Feb 2022

American Linden, *Tilia americana*, by DonArnold Feb 2022

Tree buds remain dormant through the winter. In spring, as daylight lengthens and temperatures start to warm, buds will burst open. Buds contain the beginnings of a leaf, a shoot, or a flower. Terminal buds, located at the ends of branches, grow into new shoots. Lateral buds, growing along the sides of branches, produce either vegetative shoots or flowers.

*Ginkgo biloba* flower by Karren Wcisel 2004

Lateral buds that grow into flowers are well camouflaged and easy to miss. Frequently, flowers are dark red or green in color and are quite small, easily blending into the foliage. Many trees are wind pollinated, so there is no need for the flower to be showy. Once the flowers are pollinated, they quickly die; many only live for a few days.

Bur Oak shoot, 23 inches last year, by DonArnold Feb 2022

Terminal buds appear at the ends of branches and will create new shoots, allowing the branches to grow longer. These buds release a hormone named auxin that slows or prevents the growth of lateral buds on the same branch, so all of the energy for that extension of the tree goes into growing new wood. Arborists may prune terminal buds before they open to stimulate lateral bud development, thus controlling the shape of a tree.

Miyabe Maple, *Acer miyabei*, by DonArnold Feb 2022

Many buds are covered with scales. These are small, modified leaves that protect the bud in winter against cold, freeze damage, and drying. Buds contain stored energy in the form of sugars and nutrients to be used as soon as the buds burst in spring. This makes buds attractive as a winter food source for aphids, cedar waxwings, finches, squirrels and deer. Trees can lose some of their buds, but excessive predation could stunt tree growth.

Ginkgo bud & bark, *Ginkgo biloba*, by DonArnold Feb 2022

Red oak, *Quercus rubra* by DonArnold feb 2022

Freeman maple, *Acer fremanii*, by DonArnold Feb 2022

As you are out walking in the next few weeks, you will be able to see many trees with their buds getting ready to open. You may want to take along a field guide that describes characteristics of tree buds that can be used in winter tree identification. Two good ones are Winter Tree Finder by May Theilgaard Watts, and The Tree Identification Book by George W.D. Symonds. Both describe tree bud shape, color, size, and orientation, in addition to other tree parts.

Bark, pt.3

Bark provides protection for the tree from organisms trying to get under it to lay eggs and let larvae grow, to live out of the elements, or to feed. Whether bark is thick or thin, there are areas of good protection and areas of weak protection. Weak areas may include lenticels, cracks, branch junctions, wounds, broken branches, or open spots created by fire, frost, or other environmental actions. Many trees are weakened by drought and poor nutrition increasing the likelihood that the bark will not provide protection over the entire exterior surface.

Southern Live Oak tree by Thomas Cizauskas, July 2018

Broken branches after a storm by Indiana Public Media, January 2011

A mature tree can provide food and shelter for dozens of species, but not all visitors are harmless. Dutch Elm disease is caused by a fungal bacteria found on non-native beetles introduced to the U.S. through the landscaping trade in the early 1930s. Native elm trees had no defenses, and native elm beetles also picked up the fungus and spread it further.

Tunnels made by Emerald Ash Borer by Jessica_MCP, April 2010

Camponotus castaneus, Red carpenter ant, by Katja Schulz, October 2016

Pileated woodpecker by Dennis Church, January 2019

Insects that lay eggs under bark cause very little damage, but their larvae burrow through the cork layer, sometimes creating extensive tunnels that can damage the tree’s circulatory system. Where tunnels break through the surface, decay sets in. Carpenter ants feed on the decaying wood, opening the wounds further. Woodpeckers, especially the pileated woodpecker, feed on the carpenter ants, excavating wood to get to more ants. Tree sap, leaking from the damaged circulatory system, draws even more insects, and the cycle of damage continually worsens.

Beaver damage by Steve X. O’Neil, June 2009

Many animals feed on sap and inner bark in late fall and winter when food resources are scarce. This is also the time of year when the tree is least able to defend itself. Red squirrels and porcupines bite through bark on beech and maple to get to the sap. Beavers break through the outer bark of willow, aspen, poplar, and cottonwood to eat the inner bark. Native Americans and settlers harvested the inner bark of hemlock and pine to make flour. Deer, moose, and black bears strip bark to mark their territories.

Study of a tree trunk in rain by Denish C, October 2014

Many organisms use significant parts of a tree without harm. Peeling bark is used by birds for nest building. Smooth patch disease, easily observed on white oak, is caused by a fungus eating the exterior bark, but not penetrating to the inner bark. Insects move along bark cleaning up moss, lichen, and other material that may be clogging lenticels. Their presence attracts ants, spiders, and other predators. When it rains, water flowing down the bark carries minerals, nutrients, and organic matter from plants such as lichen and moss, plus fecal matter from bark dwelling insects, and washes it all into the root area providing additional resources to feed the tree.

Canker in tree trunk by Scot Nelson, October 2014

Tree trunk burl by Scot Nelson, October 2014

Trees have their own chemical and mechanical defenses to repel, isolate, and kill various organisms. Resin seals wounds to prevent desiccation and infection. The inner bark of black cherry contains hydrocyanic acid to repel bacteria, a chemical long used in cough drops. Tannin refers to a variety of compounds found in many plant species that is used to deter epiphytes, insects, and fungi. Trees may grow inner bark tissue to form a walled off area that isolates an organism that has breached the exterior bark. This area, covered by callous tissue sealing off the wound, is known as a canker, and results in a visible patch on the outer bark. Burls forms from abnormal wood growth around these areas.

Bark is an important and integral part of all trees, as well as a complex subject with much information still to be learned. There are several good resources available for further study, including Bark, A Field Guide to Trees of the Northeast by Michael Wojtech. As you are walking the woods this year, take some time to think about the role of bark not only in tree identification, but as a resource for the woodland habitat.

Bark pt.2

Ecology is the study of the relationship between organisms, each other and their environment. Bark is a highly visible part of a tree. By observing the color, thickness and function of the bark we can learn about the environmental factors that affect trees. These may include food production, fire, water availability, sunlight, wind, weather, and temperature.

Green layer under bark by Sheila Sund, August 2007

Food production occurs through photosynthesis in tree cells that contain chlorophyll. These cells are most often associated with green leaves, but many trees with smooth, thin, or peeling bark have these cells in the cork skin layer immediately below the outer bark layer. Sunlight can penetrate thin bark even on days where temperatures are below freezing. Warmth generated by sunlight on south or southwest sides of a tree will start photosynthesis. Trees growing in habitats with less than ideal growing conditions due to too much shade, a shorter growing season, or higher altitudes can depend on this secondary source of food production.

Rough bark of white oak, Quercus alba, by Doug Goldman, USDA NRCS Cape May PMC (NJPMC), United States, North Carolina, Guilford Co, Greensboro Oct 2011

Smooth bark of American beech, Fagus grandifolia, by Bruce Kirchoff, September 2010

Bark’s outer layer is made of dead cells filled with air. When combined with thickness, color, and density, these factors determine the effects of temperature fluctuations occurring from several sources. In winter, melting water from ice or snow can flow into any opening in the bark. When temperatures fall, rapidly drying and cooling bark refreezes the water causing it to expand and put pressure on the bark to create or enhance cracks or to pry the bark loose from the tree. Normally this promotes additional bark growth, but when repeated often over a short period of time, the tree’s appearance will become rougher with an increasingly uneven surface. Similarly, lightning changes the moisture content of bark into instant steam, splitting and blowing off sections of bark. Smooth bark species are much less affected as the energy follows the sheet of water down the smooth bark and into the ground.

Quaking aspen, Populus tremuloides, by Laura Bojanowski, October 2013

Sunlight is another factor both positively and negatively affecting a tree’s appearance. In winter, southward facing bark exposed to direct sunlight can heat to over 70 degrees. As the sun sets, dropping temperatures can cause bark to shrink around a still warm and expanded inner core resulting in stretching or cracking. This may also occur in trees subjected to hot sun and cool nighttime temperatures after bark has been dried out due to drought, reducing its ability to stretch. Some species with thin bark will reflect sunlight rather than absorbing it. Bark of the quaking aspen rubs off in powdery form that reflects sunlight well enough that Native Americans used the powder as sunscreen.

Paper birch, Betula papyrifera, by bambe1964, April 2010

Pitch pine, Pinus rigida, by StillRiverside, May 2015

Fire is a familiar environmental hazard. The best protection from fire comes from bark composed of several layers. Ridges, scales, plates, and furrows also contribute to keeping temperature fluctuation small on the inside of the tree. They have an uneven surface that retains moisture and makes them more resistant to the effects of fire. Trees growing in hotter, drier climates and more exposed to fire grow bark faster than other species. Pitch pine inhabits drier areas of the northeast U.S. and has bark that thickens at an early age and contains epicormic buds that sprout into new branches after exposure to fire. Some species have a different strategy for fire. Quaking aspen has thin bark that burns easily, but the trees resprout quickly and often from old rootstock. Paper birch also burns easily, but puts out a much greater quantity of seed annually than other species in the same habitat.

Hackberry, Celtis occidentalis, by Jimmy Smith, October 2009

American elm, Ulmus americana, by Matt Lavin, August 2010

Shagbark Hickory, Carya ovata, by Eli Sagot, March 2007

The environment places many stresses on the external layers of trees. Form, function, and appearance is initially determined by DNA, but is continually being modified by location and external forces. As you get outside or look out your window, try to identify the environmental factors affecting your trees. Next week, our final look at bark will deal with impacts from other organisms on trees.

Bark, pt.1

It has been cold outside for the last few weeks; and whenever we go outdoors, we tend to bundle up with warm coats, gloves, hats, boots, and long underwear. Animals and plants have their own strategies for living through the winter, including trees. Bark is an essential part of any tree. Bark provides protection, insulation, and plays a role in getting food to the rest of the tree. Bark can be used to identify tree species from the way it grows, its color, and its texture. However, bark can look different from tree to tree, and from branch to branch on the same tree.

There are several layers to a tree. The innermost layer is called wood and is made up of dead cells from previous year’s growth. Wrapped around the wood is the vascular cambium where new cells are growing inward to become the xylem layer that transports water and nutrients from the roots upward, and new cells growing outward to become the phloem that transports sugar and nutrients from the leaves to all parts of the tree. During winter, the need for food and water is much less as the tree enters a non-growing, dormant state, but circulation continues enough to keep the tree alive and hydrated.

Bark cross section drawing by Brer Lappin, Jan 2010

Bark consists of several layers starting with the phloem, also known as the inner bark. The periderm makes up the outer layers of bark protecting the phloem and other inner layers from environmental elements. The cork skin is the first layer of the periderm, containing cells to store food and waste products including tannins and resins. The cork cambium is the second layer where new cells are growing to add to the outside and final layer, the cork. Cork, mostly hollow, dead cells, prevents desiccation, provides insulation, and is a protective barrier from fungal and bacterial diseases.

Bark’s appearance is caused by both internal and external factors including growth, gas exchange, and the environment. At what rate are new cells being added to expand the tree? Does the bark stretch? Are there cracks or breaks in the bark? Bark thickness may vary from one-quarter inch on a mature beech to over an inch on a mature oak. Are there visible openings in the bark? Lenticels are specialized cells in the bark allowing an exchange of gases with the outside environment. Is temperature speeding or slowing growth? Has fire influenced the area? What affect has the wind had? Has the tree been attacked by bacteria, fungi, or animals? Have other plants used or damaged the tree?

Six bark appearance categories are commonly used to distinguish trees:

Smooth: Cork maintains a constant thickness throughout the life of the tree, and old cells slough off easily. An example is the American beech, Fagus grandifolia.
Horizontal peel: Expansion causes the external layer to peel away in strips when it is still quite thin. An example is river birch, Betula nigra.
Visible lenticel: Often a different color than the bark, lenticels can be oval, round, linear, or diamond-shaped. Some retain their shape over time, while others stretch as the tree grows. An example is pin oak, Quercus palustris.
Vertical cracks: Cracks often begin at lenticels, and they may be a different color depending on the color of the phloem layer that is exposed below. An example is pignut hickory, Carya glabra.
Scales, plates, or vertical strips: Each of these structures are separated on one or more sides from one another, and appear as overlapping sections of a similar size. Examples include black cherry, Prunus serotina, and American sycamore, Platanus occidentalis.
Ridges and furrows: As trees with hardened cork expand, the cork begins to crack. Sections are held together by fibrous tissue, creating furrows between ridges. Examples include Eastern cottonwood, Populus deltoides, and bur oak, Quercus macrocarpa

As you walk in the woods this season, consider taking along a tree guide to see how many trees you can identify by their bark. In a future installment on ecology, we will take a closer look at the role bark plays in the relationship between trees and their environments.

Smooth bark of *Fagus grandifolia*, American Beech by Derek Ramsey, Mar 2016

Horizontal peeling of *Betula nigra*, River Birch by Greg Hume, Feb 2016

Visible lenticels of *Quercus palustris*, Pin Oak by Dodshe, Aug 2011

Vertical cracks of *Carya glabra*, Pignut Hickory by Plant Image Library, Dec 2015

Plates of *Prunus serotina*, Black Cherry by Chhe, May 2009

Scales or vertical strips of *Platanus occidentalis*, American Sycamore by Rosser1954, Mar 2008

Ridges and furrows of *Populus deltoides*, Eastern Cottonwood by Cohee, Sep 2018

Ridges and furrows of *Quercus macrocarpa*, Bur Oak by Chhe, Jun 2009

Lichens

A lichen is a composite of two organisms, a fungus and an alga, living together with both providing benefits. Algae can survive on their own in saltwater or freshwater habitats. They can also survive in land-based habitat as part of a lichen. Fungi cannot produce their own food and can only survive by depending upon another organism for their nutrition. Many fungi are decomposers, depending on absorbed nutrients from dead or dying plants, but some form relationships with other organisms such as algae, which can photosynthesize food for both partners.

Hooded Sunburst Lichen, Xanthomendoza fallax by Samuel Brinker, Jan 2018

Lichens grow in a variety of habitats. Lichens cannot retain water, but they can absorb it from a standing or flowing source, including water vapor from the atmosphere. When a lichen is dry, it is in a dormant state, and when wet, it is in a growing state. Poikilohydry is the process of freely alternating between these two states. Lichen also require clean, fresh air. They absorb many of the compounds present in the atmosphere. Nutrients needed include carbon dioxide, oxygen, and nitrogen. Nitrogen in the atmosphere is in an unusable form. It must first be “fixed” – changed into a form that lichens can absorb and utilize. This is accomplished by various types of algae with this capability, such as cyanobacteria. Algae use light in the presence of chlorophyll for photosynthesis to create food to feed both organisms. The spectrum of light as well as the quantity of light received determine the color of lichen. Every lichen needs a substrate, or anchor point, that provides a surface that does not move for the time it takes the lichen to form on it.

Candleflame Lichen, Candelaria concolor by John Boback, Jan 2021

Lichens come in three distinct forms, adding color, texture, and beauty to their environment. Foliose lichen appears as a cluster of leaflike shapes, with two distinctly different sides. Fruticose lichen are hairlike or cuplike, with branches coming from a central core. Crustose lichen form a crusty surface, often present in bright colors. There are 20,000 known species of lichen that cover 6%-8% of the Earth’s surface. More than 200 species have been documented in DuPage County. Their lifespan is difficult to determine, but an arctic species called map lichen has been carbon dated to 8,600 years old. They have also been taken to outer space and resumed normal growth after being returned to Earth.

Rock Candy, Botryolepraria lesdainii by Tomas Curtis, Apr 2017

Lichen use photosynthesis to convert carbon dioxide into oxygen in every environment. However, their greatest threat is air pollution. They absorb most compounds found in the atmosphere including heavy metals, carbon, sulfur, and other pollutants. Scientists are able to measure each compound in lichen and in the surrounding habitat. Using this data, the U.S. Forest Service is able to determine actions to recommend for mitigating air pollution.

Star Rosette Lichen, Physcia stellaris by Nova Patch, Jan 2019

Lichens are a major food source for many animals living in areas where food is scarce in winter, most notably caribou, flying squirrels, and red-backed voles. Some lichen have antibiotic properties under investigation for use in the pharmaceutical industry. Wolf lichen has been used by Native Americans and settlers alike for both tea and poisoned arrowheads. Many varieties are used to make dyes for clothing and baskets. Having lichen growing around you signifies clean air and water. They are easy to find and study during winter months when many low lying surfaces are no longer hidden from view. Take along a field guide on your next walk to look for and enjoy lichens in their many forms.

Wrinkled Crust, Phlebia radiata by Amadej Trnkoczy, Jan 2009

A beginner’s guide to lichens in our area can be downloaded from the Chicago Field Museum by clicking on: Common Lichens of Chicagoland

More information on how the U.S. Forest Service studies lichens and air pollution can be found by clicking on: National Lichens & Air Quality Database and Clearinghouse

Asters

Asters, a Greek word for star, bloom between early August and the first frost. The late blooming period is thought to be an adaptation to attract pollinators without competing against the majority of flower species in our area that bloom in spring and summer. In return, asters provide an important source of nectar and pollen during the latter part of the year.

Short’s aster, Symphyotrichum shortii, by Dan Mullen2009

Asters are classified by flower arrangement and leaf shape. They are all members of the composite family Asteraceae, but many of the species that live in our area have been reclassified into a new genus Symphyotrichum, due to DNA differences with those species found in the old world. Native species have both ray and disc flowers. The tightly packed disc flowers make up the center of what is viewed as the whole flower or in florescense, and the petals coming out from the center are the fertile ray florets. Seeds are wind-born and have pappus, a piece of fluff, attached to them, allowing the wind to efficiently move them over long distances.

Panicled aster, Symphyotrichum lanceolatum, by Robert H Mohlenbrock, 1989 @ USDA NRCS Wetland Science Institute

Heath aster, Symphyotrichum ericoides, by Jennifer Anderson, 2001

The calorie-rich nectar is eaten by insects bulking up for hibernation including queen bumblebees, hoverflies, and several ant species. Migrating butterflies, including monarchs, depend on the nectar for quick energy for their long travels. Pearl crescent and painted lady caterpillars feed almost exclusively on aster leaves to fatten up before pupating. Many backyard bird species over-wintering in this area eat the seeds including American goldfinch, tree sparrow, black-capped chickadee, pine siskin, and song sparrow.

Expressway aster, Symphyotrichum subulatum, by Robert H Mohlenbrock, 1995 @ USDA NRCS Wetland Science Institute

Calico aster, Symphyotrichum lateriflorum, by Robert H Mohlenbrock, 1989 @ USDA NRCS Wetland Science Institute

Hairy aster, Symphyotrichum pilosum, by Jennifer Anderson, 2001

Pictured with this article are many of the large variety of asters in bloom around the area. Consider taking a walk in area woodlands to see Drummond’s aster, calico aster, heart-leaved aster, and Short’s aster. A walk across the prairie may yield sights of rush aster, bushy aster, blue aster, heath aster, New England aster, and hairy aster. You can also observe in fens and marshes panicled aster, shining aster, and bristly aster. And even as you are driving home, be watchful for the expressway aster, which can easily tolerate the salt spray along the embankments of many byways.

Seeds

Autumn is the time for many plant species to spread their seeds before dying or entering dormancy for the winter. Every seed is a potential new plant, but it is unable to move on its own. Seeds must rely on wind or water or animals or gravity. There are several ways that seeds leave the parent plant and move to new locations. These methods are described below including examples of plants that you can observe on your local walks in the coming weeks.

Jack-in-the-pulpit, Arisaema triphyllum by Don Arnold 2021

Seeds are contained inside the fruit of plants. The size, shape, texture and presence of special structures on both the fruit and the seed contribute to the method of travel. Some fruits travel on their own, carrying the seeds with, but many ripen while still on their host plants, then split open and allow the seeds to travel by themselves. Seed and fruit surfaces may contain spines, glues, fluffs or hooks that aid the seed in its travels.

Common dandelion seed, Taraxacum officinale by Patrick J Alexander

Black maple seeds, Acer nigrum by Steve Hurst, ARS Systematic Botany & Mycology Laboratory, PA

Wind can move seeds a short distance or many miles depending on the air speed and direction. Winged fruits containing one or more seeds are pulled down by gravity while being carried short distances by the wind. A childhood favorite, the “helicopters” from maple trees, recently fell. Others using the wind are lightweight fruits and seeds with a cotton-like, feathery plume attached that can travel great distances on windy days. Examples include fruits of the quaking aspen and seeds from milkweed, thistle, and dandelion. Small, extremely light seeds may be carried on their own by even a light breeze. Eastern prairie-fringed orchid and poppy seeds are dust-like in form, and are easily whisked away from flower heads by any air movement.

Bur oak acorn, Quercus macrocarpa, by Steve Hurst, ARS Systematic Botany and Mycology Laboratory, Georgia

Animals, including humans, move many seeds, sometimes unknowingly and other times with a purpose. Some species of plants have an aril, a small food treat, attached to each seed. Insects will carry seeds back to their nests to eat the aril, but discard the seed. Ants move hundreds of yellow dog tooth violet and Jack-in-the-pulpit seeds every autumn. Many seeds are contained in fleshy fruit eaten by animals that later excrete the undigested seeds elsewhere. Fruits harvested by humans are moved indoors or to local farmers markets and grocery stores. How many of you have apples, strawberries and apricots at home? Nuts and acorns have a leathery covering containing one or more seeds and are often cached by birds and squirrels for the winter, then forgotten and left to germinate in spring. Many fruits are covered with barbs and hooks that attach to animal fur or human clothing as the plant is brushed against.

Ticktrefoil, Desmodium seed with barbs by Janet Tarbox, 2012

Sycamore seed, Platanus occidentalis by Amehare, 2006

Many plants that grow near water, including oceans, lakes, and rivers, grow corky fruits containing air spaces that allow the fruits to float and travel with the water currents. Sycamore and water lily are two examples. Coconut palm originated in the South Sea Islands, but can be found growing on most tropical shorelines around the world. One last travel method is used by explosive fruits that burst and shoot out their seeds for several feet in all directions. Look for spotted touch-me-not, lupine and plants in the bean and pea families.

Heirloom poppy seed, Papaver paeoniflorum by Don Arnold, 2021.

Big seeds often travel short distances and small seeds may travel far away. Round seeds move across the uneven terrain and flat-sided seeds stay wherever they initially land. If every seed fell beneath its parent plant, competition for resources would become fierce, and many plants would die. It is important that seeds can move about, finding suitable locations to grow over a wide area contributing to the natural diversity of habitats.

Acorns

As I am out walking at this time of year, whether in the woods or around the neighborhood, there is lots of crunching underfoot. Acorns are one of the larger seeds littering the paths. There are about 450 species of oak trees worldwide and almost 90 in the United States with 17 native to Illinois.

An acorn is a fruit and a nut and a seed. Among Illinois species of oak trees, acorns grow between 5/16″ and 1-1/8″ in diameter, although many larger ones up to 3″ in diameter can be found in other parts of the world. One quarter of the seed is covered in a cupule, a saucer shaped cup that may or may not be fringed around the edges. The leathery shell, called a nut, is a hard, dry pod that surrounds a fruit with a single seed inside. Oak trees are in the genus Quercus in the beech family, Fagaceae, and are split into two sub-genera, white oaks and red oaks. White oak acorns grow to maturity each autumn when they fall off the trees. Red oak acorns are produced yearly, but have a two year growth cycle before maturing and falling off the tree.

Mast is the accumulated fruit of trees and shrubs in forests, and acorns play an important part in oak-hickory dominated woods. They are large, easy to find and eat, and are rich in nutrients including protein, fats, and carbohydrates, plus the minerals calcium, phosphate and potassium and the vitamin niacin. White oak acorns are relatively sweet compared to the bitterness of red oak acorns. Both contain tannins, a compound that makes food taste bitter and may be toxic in large quantities. Animal species that eat red oak acorns typically cache them until water running over the cached nuts has leached out most of the tannin. Acorns in the Midwest are a favorite food for duck, turkey, quail, pheasant, squirrels, chipmunks, deer and bear.

White oak acorn, Quercus alba, by Steve Hurst, ARS Systematic Botany and Mycology Laboratory, Georgia

Acorns have never been used for human food on a scale reaching other nut varieties, but can be used for a variety of recipes. In times of famine, they were a staple for Greek and Japanese cultures. Korean noodles have been made from acorn flour since the early 1600s, while Ersatz coffee was made from large quantities of acorns during the Civil War. Acorns, which contain starch, can be ground into flour for bread, pastries and pasta. But all acorns require some leaching, involving soaking in several baths of clean water, to remove the tannins. Hot-water leaching or boiling acorns can accomplish this in three to four passes, but it also removes the starch necessary to hold the resulting flour together. Cold-water leaching takes a few days, but yields a better flour for baking.

Acorns are large and oak trees must rely on animals to move their seed around. Scatter-hoarding is a behavior used by jays and squirrels that gather acorns and cache them for later consumption. If the animal does not remember where all of its caches are, or it should perish before consuming all of the stored food, the remaining acorns have a chance to sprout and grow. Every six to seven years, often referred to as mast years, oak trees will produce many times more than the usual number of acorns. Current theory suggests that this is an attempt by the trees to overwhelm the consumers and increase the acorns chances of sprouting. Take your favorite tree field guide and get out to a forest near you to see what acorns you can find and identify the trees that are nearby.

Autumn Grass

In autumn, we think about the spectacular colors of the changing foliage. Ornamental grasses found in prairies, gardens and woodland edges are also showing shades of red, tan, and gold. They are part of the foundation of native plant species that cover prairies, savannas and meadows throughout the greater Midwest, and they are an important component in restoration projects and backyard gardens.

Indian grass, Sorghastrum nutans, by Brett Whaley, 2017

Grasses are classified as either cool-season grasses, which green up in early spring and go dormant by early autumn, or warm-season grasses which start actively growing after the soil is warm, typically from June 1st through late autumn in northern Illinois. Six of the most common warm-season grasses native to this area include prairie dropseed, Sporobolus heterolepis, Northern sea oats, Chasmanthium latifolium, little bluestem, Schizachyrium scoparium, switchgrass, Panicum virgatum, Indian grass, Sorghastrum nutans, and big bluestem, Andropogon gerardii.

Northern sea oats, Chasmanthium latifolium, by Robert H Mohlenbrock, 1989 @ USDA NRCS Wetland Science Insititue

Big bluestem, Andropogon gerardii, by Matt Lavin, 2015

Indian grass seedheads, Sorghastrum nutans, by Joshua Mayer, 2014

All of these grasses are native to Illinois and exhibit several common characteristics. Flowers are small, with stamens and stigmas exposed to the air. They have no nectar, but produce large amounts of smooth, light pollen that is easily carried away by any air movement. These grasses prefer full sun, but may grow in bright shade. They like moist conditions in well-drained soil, and are tolerant of rocky soil and drought. All of these species spread by dropping seed and a few also send out long, densely packed, underground root systems.

Switchgrass seed, Panicum virgatum, by Matt Lavin, 2015

Switchgrass, Panicum virgatum, by Matt Lavin, 2009

Grasses provide sustenance for many species finding their food sources dwindling at this time of year. Grasses can be cultivated or found growing wild in areas where it is available to cattle, bison, and horses. The foliage is also favored by a large number of insects including grasshoppers, leafhoppers, aphids, thrips, katydids and walking sticks. Several species of skipper caterpillars can be found among meadow and woodland edge grasses. Along with the great quantities of seeds being produced, the insects serve as a food source for grassland bird species.

Prairie dropseed, Sporobolus heterolepis, by Joshua Mayer, 2015

Prairie dropseed displays pink and purple flowers in late summer with a faint odor of buttered popcorn. It is a long-lived plant but hard to propagate, which is normally accomplished by subdividing each of its tufts. Northern sea oats is easily grown and has become a favorite of gardeners, although it can become an aggressive spreader. It is often used in flower arrangements for the large, flat seeds and leaves. Little bluestem is a common grass of rocky and thin soil areas. It is widely used in both restorations and gardens for its drought resistance and its spectacular blue and red palette. Big bluestem has earned the nickname of “turkeyfoot” due to the way the mature seed heads display at the end of tall flower stalks. Indian grass also grows tall and straight and maintains that posture throughout winter’s cold and wet weather. It is used as cover by Ring-necked Pheasants, Greater Prairie Chickens, Northern Bobwhites, and Field Sparrows. Switchgrass, another species that stays upright when wet, also provides winter cover for prairie deer mouse and house mouse. It has been evaluated as a source of alcohol for use as an alternative fuel. More alcohol per acre is generated by switchgrass than corn, and it is a perennial, but it is bulkier than corn making shipping and storage more costly.

*Little bluestem, Schizachyrium scoparium, by Patrick Alexander, 2011*

Native grasses are an integral part of the landscape of northern Illinois, providing food, shelter, and protection for many birds, insects, and mammals in autumn and through winter. With airy flower stalks, tall waving leaves, and striking colors of red, bronze, and gold, grasses add visual interest into every landscape.

Northern sea oats, Chasmanthium latifolium, by Scott Zona, 2021

Silphiums

In the late summer, there are lots of bright colored flowers to see, and among the showiest of these are the four silphium species. Including compass plant, Silphium laciniatum, prairie dock, Silphium terebinthinaceum, cup plant, Silphium perfoliatum, and rosinweed, Silphium integrifolium, they stand tall with bright yellow daisy-like flowers that wave in the breeze. The name silphium comes from Greek meaning a resinous plant. The four plants we will look at today are found in a variety of habitats, and are all easily grown in our gardens.

Silphium perfoliatum, cup plant by Kerry Woods, 2007

Silphium perfoliatum, cup plant by Scott Zona, 2005

The cup plant likes sun and moist soil and can be found along stream and river edges, as well as in open woodlands and savannas. It is 4′-10′ tall, with a single, four-sided stem that only branches for the multiple flowers it supports. Leaves are opposite, about 4″x 8″ and join together on one side around the stem, forming a cup-like structure capable of holding water. Cup plants grow in large colonies providing an area for birds to rest out of the hot sun while searching for insects among the foliage and having drinking water readily available in the cups.

Silphium terebinthinaceum, prairie dock by Joshua Mayer, 2010

Silphium terebinthinaceum, prairie dock by Scott Zona, 2019

Prairie dock is found in wet or dry savannas. It has a vase-like cluster of leaves at the base of the plant with flowers on naked stalks from 3′-10′ high. A stout taproot extending nearly 12′ deep supports the plant. They prefer full sun and moist soil, but can tolerate drought well. Prairie dock often displays large, glossy black blotches on its foliage. These are formed by leaf beetles that lay their eggs on the leaf and cover them with a sticky substance that dries to a hard shell for protection. After the eggs hatch, the larvae will eat the leaf underneath while protected from above.

Silphium laciniatum, compass plant by Joshua Mayer

The compass plant, another species with a long taproot, grows 6′-12′ tall with leaves along the whole stem that gradually get smaller towards the top. A mature plant can live over 100 years, exhibiting up to 30 flowers in late summer for about six weeks. Young compass plants will align their leaves from north to south so they receive the cooler morning and evening sunlight. As early settlers crossed the prairie, they tended to use the alignment of the leaves for finding their way. However, older plants do not turn their leaves as readily, much to the woe of many wayfarers.

Silphium integrifolium, rosinweed by Frank Mayfield, 2006

Rosinweed has the shortest stature, standing 3′-5′ tall with a stout, central stem that branches at the base of the flowers. This is the only one of the four with a fragrant scent from the flower. Although it grows in sizable clumps, it is not an aggressive spreader from underground roots. Most clumps are composed of individual plants. The seeds are a favorite of goldfinch.

Silphium perfoliatum, Cup plant by Steve Hurst, ARS Systematic Botany and Mycology Laboratory, NJ, USDA-NRCS Plant Database

All of the silphiums are similar in appearance, with yellow flowers growing on tall stalks. They bloom in mid to late summer for four to six weeks. They are easy to maintain and resistant to drought, but may have a tendency to topple over when planted on slopes exposed to heavy wind. All are native to Illinois. Their foliage is rarely consumed by small mammals due to its coarse texture, but may be eaten by larger herbivores, including cattle. The disk florets, inner part of the flower, are sterile, while the ray florets, outer parts, are fertile. This is the exact opposite characteristic of that found in sunflowers.

Silphiums are a favorite of pollinator species including honeybees, bumblebees, miner bees, and ruby-throated hummingbirds. The flat, dark brown seeds are especially favored by goldfinch. Consider adding one or two of these plants to your garden for a bright background display.

Dead Trees

Trees offer a variety of services for wildlife, whether they are in a forest, a city park, or in your backyard. Trees grow slowly and die slowly. Each year, they flower, leaf out, and grow fruit throughout the spring and summer and then drop leaves and fruit each autumn. Often, one, two or more branches will die each year, even as new ones are being added. As each part of a tree dies, habitat is not lost; it is transformed into use for a variety of wildlife.

White oak snag by Frank D. Laspalluto, 2021

A hole in a tree can be created by a variety of events: branches broken off by weather or animals, trees being impaled by other trees during violent storms, or punctures or cuttings from human activities. Openings offer nesting sites for owls and flying squirrels. Bark at the lip of a hole will start to peel away allowing bats and spring peepers to get underneath for shelter. Small holes invite insects in, and woodpeckers searching for insect prey enlarge the holes. When a cavity becomes large enough to kill the entire tree, it is often used by tree swallows for nesting or as a great place for honeybees to build hives.

Red-shouldered hawk couple in the early morning light at the Venice Rookery, Venice, Florida, Lookout post by Diana Robinson, 2020

Snags are dead trees that remain standing. These offer birds of prey perches while they scan the areas underneath for small animals to hunt. After the snag becomes too weak to stand any longer and falls to the ground, it becomes shelter for numerous species. Mice and chipmunks use small holes to store food, raise young, and hibernate in for the winter. Large hollow logs offer a home for skunks and bobcats. Accumulated bark and leaf litter is a favorite place for toads and black rat snakes looking for a place to lay eggs. Shade provided under fallen logs promotes a damp environment, a favorite place for salamanders.

As wood starts to decay, decomposers move in. Fungi begins the process by breaking down the bark and returning the nutrients to the soil. Millipedes, termites, beetles, and ants all feed on rotting, decaying wood. Opossum, raccoon, robins and nuthatch find a treasure of insects and arthropods to feed on. Earthworms and grubs help to mix all of the droppings around the fallen log into the soil through their tunnel building activities, constantly enriching the soil.

Shelter for two by Lars-Goran Hedstrom, 2015

Dead trees are an important part of a forest ecosystem and can play a beneficial role in any habitat. Consider leaving branches where they drop, or artfully placing them into your own garden habitats. They provide shelter and food for many organisms, creating a rich and diverse community. Species that directly use the wood provide food for small organisms as they break down the wood and are prey themselves for larger animals. They release the nutrients trapped in the wood and enrich the soil in the process. They create shelter by opening new holes and enlarging existing ones for additional plants and animals to occupy. Next time you are out walking, gently turn over a log, and observe this wonderfully changing habitat.

Dangerous Plants

It’s summer and a wonderful time for hiking in fields and forests, observing the plants and animals that live here. But as you are out enjoying nature, there are dangerous plants to be aware of. Some species can also be found in backyard gardens where they may pose a hazard to people and pets. Here are three to avoid.

Poison hemlock, Conium maculatum by William & Wilma Follette, 1992 USDA NRCS

Poison hemlock umbrel, Conium maculatum by Doug Goldman, 2011 USDA NRCS

Poison hemlock stem, Conium maculatum by Doug Goldman, 2011 USDA NRCS

Poison hemlock, Conium maculatum, is native to Europe and North Africa but is widely distributed in North America. The plant can grow to 12′ tall on a hollow, hairy stem, green with dark maroon spots. Flowers form a small, loose, white cluster often mistaken for Queen Anne’s Lace. All parts of the plant, especially the seeds and roots, contain a poisonous alkaloid oil called coniine. When ingested, the oil works as an inhibitor directly on the central nervous system which may lead to failure of the respiratory muscles and death. Eating six to eight leaves may prove fatal for humans. If the oil comes in contact with skin exposed to direct sunlight, a phytophotodermatitis reaction occurs causing severe burns of the area.

Deadly nightshade fruit, Atropa belladonna,
by Peganum 2009

Deadly nightshade, Atropa belladonna, by Joan Simon 2014

Deadly nightshade, Atropa belladonna, another plant introduced to the U.S., has a long history of use in medicine, cosmetics and as a toxin. Plants grow to seven feet tall with purple and green, lightly scented, bell-shaped flowers. All parts of the plant, but most especially the root, contain tropane alkaloids having anticholinergic properties inhibiting the involuntary muscle movements the body depends on for functions including sweating, breathing, and heart rate. The berries are attractive, dark red, cherry-like and sweet tasting. Consumption of 2-5 berries by children and 10-20 berries by adults can be fatal. Only cattle and rabbits seem to have no reaction to the plant’s poison.

Giant hogweed, Heracleum mantegazzianum, a member of the carrot family, is native to Eurasia and was introduced to the U.S. as an ornamental in the late 19th century. This plant typically grows 6′ to 18′ tall with 3′-5′ diameter, deeply-lobed leaves. Stems are bright green with purple splashes and coarse white hairs. Greenish-white flowers, similar to Queen Anne’s Lace produce 10,000 to 50,000 half-inch long seeds per plant. Like poison hemlock, the sap causes a phytophotodermatitis reaction when in contact with skin subsequently exposed to the sun’s UV rays. Initial reactions may be mild including red, itchy skin developing into more severe blisters and burns after 24-48 hours. Scars last several years, and hospitalization for burn treatment is not uncommon.

Poison hemlock, Conium maculatum by Doug Goldman, 2012 USDA NRCS

All three species are considered weeds, found in fields and along forest edges, and may not be actively controlled or removed resulting in widespread distribution. Recently, poison hemlock has become a serious backyard problem in Ohio and Indiana where plants have been spreading rapidly. Causes for the spread are not clear, but the trend is continuing to move westward. Enjoy your nature viewing, but be aware of the plants around you and the secrets they may hold.

Cattails

Cattails are a familiar plant seen growing in wetland habitats throughout the area. Native to many parts of the world, including North America, South America, Africa and Eurasia, they provide food and protection for many species living in wetlands. Cattails are an emergent plant, with roots growing in soil underwater and the remainder of the plant emerging above the surface, into the air. Cattails prefer six to eighteen inches of water, although they can tolerate drought conditions as long as the soil remains moist.

Broad-leaved cattail, Typha latifolia by Tom Benson

Narrow-leaved cattail flowers, Typha angustifolia by Ryan Hodnett

There are two species of cattails common in Illinois. Broad-leaved cattail, Typha latifolia, and narrow-leaved cattail, Typha angustifolia, have many of the same characteristics and hybridize easily, so identification may be difficult. Stems are three feet to nine feet tall and are firmly anchored in the wet soil by a complex system of fine, tentacled roots; they are flanked by slightly shorter, narrow, upright, olive-green leaves. Separate groups of male and female flowers grow at the top of the stem. Yellow male flowers are located at the tip above a thick, velvety cluster of dark brown female flowers. The male flowers of broad-leaved cattails grow immediately above the female flowers, but on narrow-leaved cattails there is a space of several inches between the two groups.

Broad-leaved cattail flowers, Typha latifolia by Kevin Kenny

Both cattail species live in the same habitat and are aggressive spreaders. They utilize two different reproductive strategies. Rhizomes, roots growing horizontally along the soil surface, begin to spread in autumn. They cease growth during the colder temperatures of winter, but become active again in spring. Where the rhizome comes in contact with the soil, a new clone of the original plant is started. Clonal clusters grow in tight masses of up to a hundred stems. A second reproduction strategy is wind pollination. Pollen, a male sex cell, fertilizes female flowers. Seeds are then also spread by the wind. After pollen is dispersed, the male portion of the flower spike withers and falls off. The dark brown cluster of seeds may include up to 200,000 per stem. As seeds pull away from the stem, an attached silk plume billows out behind, allowing the seed to be borne long distances on steady breezes.

a quiet canoe trip on Isobel Lake…a Marsh Wren’s (Cistothorus palustris) desk amongst the reeds…Marsh Wren nest by Murray Foubister

Wetlands provide safe habitat for many species of spiders, insects, fish, turtles, birds and mammals. The denseness of cattail clusters keeps predators out while providing small pockets for homes. The area is a favorite for marsh wren, red-winged blackbird, yellow-headed blackbird, American coot and many species of rails and bitterns. Leaves are used for building nests and muskrat lodges. Young leaves provide food for many insects, mammals and birds. The carbohydrate-rich rhizome is an important food source for muskrat and geese. Seeds are rarely eaten, but seed heads provide over-wintering habitat for several moth larvae which in turn are a spring food source for many birds.

Muskrat with cattails by Michael B Smith

Early native Americans also enjoyed cattails in their meals. Flower spikes were roasted and served like corn cobs. Pollen was mixed with wheat flour to provide a nourishing base for bread. Today, leaves are woven into chair seats, rugs, and mats. Look for stands of cattails in nearby wetland communities, and observe the other species that live among them including ferns, rushes, sedges, grasses and the many animals that call these environments home.

Fern Fun

In prehistoric times, when we had a warm, moist, and stable climate, Ferns were some of the most plentiful plants to be found. Many of those growing at that time are now extinct, but as the climate cooled, many ferns adapted to the forms we see today, numbering over 12,000 worldwide including 400 in the U.S. and about 100 in the northeastern U.S. Ferns were among the first plants with vascular systems containing an internal system of tubes allowing for water and nutrient movement throughout the plant and providing support for an upright stance. There were no flowers, and their reproductive process, using spores, was not discovered until the late 1600s and not well understood until the mid-1800s.

Christmas fern, Polystichum acrostichoides, by Sandra Richard

Leaves, called fronds, have specialized cells on the bottom side called sporangia that produce spores. Sporangia first appear as small white or green dots, but as spores mature over time, they turn shiny and dark brown. Several hundred thousand to several million spores are created by each fern. When they are mature, spores are ejected by a variety of methods from being shot into the air to simply floating away on a slight breeze. If they do not land in a favorable environment, they can remain viable for up to a year.

Adder’s tongue fern, Ophioglossum pusillum, by Odd Wellies

The reproductive process, called alternation of generations, has both sexual and asexual components. In the asexual process, spores grow by dividing and forming a small structure called a prothallium that gets its water and nutrients directly from the soil. The prothallium divides into two more structures, the archegonium, containing an egg, and the antheridium, containing sperm. In the sexual process, sperm swim to the eggs, fertilize them, and a new plant begins to grow. The young fern, also known as a fiddlehead, is a tightly coiled collection of new fronds that pokes through the soil surface in spring. As growth continues, the flat, green fronds uncurl and have many leaflets on either side of a midrib stalk. Photosynthesis takes place in the fronds, producing food for the plant.

Walking fern with spores, Asplenium rhizophyllum, by Doug McGrady

*Walking fern, Asplenium rhizophyllum, by Patrick Alexander*

Spores represent the normal process for reproduction in most ferns, but some can reproduce strictly asexually by cloning of fronds, roots, or rhizomes. The walking fern, Asplenium rhizophyllum, a rare species found in dolomite canyons around Lake Michigan, are an example of cloning as they tip their fronds over till they touch the ground and start a new plant.

Interrupted fern, Osmunder claytoniana, by James St. John

Ferns come in a variety of sizes, from two inches to eight feet tall. They grow in most habitats, although they are rare in deserts. There are several ferns growing in the DuPage area that you may enjoy finding and learning about. The Christmas fern, Polystichum acrostichoides, is an evergreen plant growing in rich, moist wetlands and forests. Adder’s tongue fern, Ophioglossum pusillum, is found in fens and marshes, particularly areas with sandy or gravelly soil. Interrupted fern, Osmunder claytoniana, which got its name from the Saxon god, Osmunder the Waterman, who hid his family under the fern while fleeing his enemies, can be found on woodland slopes where there is seepage. Look for these as well as other species to enhance your hiking experiences.

Trillium

Take a walk in any woodland at this time of year and there is a multitude of wildflowers growing on the forest floor. The genus trillium, in the lily family, includes forty-three species worldwide and thirty-eight that can be found in North America, most east of the Mississippi River.

Trillium flowers come in a variety of colors including white, yellow, pink, red, purple, and striped. When mature, all parts of the plant are in multiples of three including bracts, sepals, petals, anthers and ovules. All species are herbs that grow from seed or by sending out roots to start new plants. In biological terms, there are no true leaves nor stalks. Only the flower and bracts, usually identified as leaves, are visible aboveground, existing as extensions of the root. The bracts do function like leaves including photosynthesizing food for the plant.

Prairie trillium, *Trillium recurvatum* by DonArnold

Prairie trillium detail, *Trillium recurvatum* by DonArnold

Prairie trillium, Trillium recurvatum, likes wet or dry woodlands and savannas. Flowers are at the ends of 6″-15″ tall stems surrounded by three green bracts. The flower has three triangular, dark maroon sepals containing six stamens with black anthers. A single fruit develops with several small, dark brown seeds. Variations of this plant have been found with yellow petals and purple anthers.

Toad trillium, *Trillium sessile*, Smithsonian Institution, Richard A. Howard Collection @ USDA-NRCS PLANTS Database

Toad trillium, Trillium sessile, is found in the southern portion of DuPage County and further south in Illinois. Growing on bluffs and banks of streams and rivers, it is uncommon in dry woodlands. Sessile flowers, a term referring to a flower developing directly on top of the bracts, are dark maroon containing six maroon and yellow-striped anthers. Ovules develop into a three-celled white to purplish-green fruit with several seeds in each cell.

Large-flowered trillium, *Trillium grandiflorum* by Joshua Mayer

Large-flowered trillium, Trillium grandiflorum, has become less common over the last few decades. It is found in wet or dry woodlands and savannas. 8″-18″ tall, it produces a single flower 2″-4″ across composed of three white petals set against three green sepals. The flowers slowly turn pink as they age. Possibly due to the more showy appearance, this plant is readily browsed by deer. When found in colonies, the large leaves can form shelter for small mammals such as field mice and shrews.

Declined Trillium, *Trillium flexipes* by Dan Mullen

Declined Trillium, Trillium flexipes, is found in wet or dry woodlands, particularly in oak dominated areas. Growing up to 2′ tall, a single white flower is produced on a nodding peduncle of a mature plant. About 2″ across, the flower is three white petals and three green sepals surrounding six light yellow anthers. The flower hangs downward a little above or below the bracts. A six-angled seed capsule replaces the flower in late summer.

Trillium seed with elaiosome, by Danny Najera

Trilliums develop very slowly, often taking several years to develop into a mature plant able to produce flowers and seeds. During summer heat and drought, plants may go dormant, retreating back into the thick root. Because of this slow growth rate, trilliums are not often found in nursery sales. Each year as a new shoot is sent up from the root, a ridge forms where the new bud grows. Counting the ridges on a root can give a good indication of the age of the plant. Many plants have been found that are several decades old.

Ant with trillium seed and elaiosome, by Danny Najera

Trilliums spread by seeds that contain an elaiosome, a white, fleshy container of nutrients attached to each seed. Favored by ants and wasps, this nutritional package is taken to feed their young while the seed is ignored. Ants nesting in soil mounds or decomposing wood and yellow-jacket wasps nesting underground all help to move seeds around.

Spring is lasting a little longer this year with the cooler temperatures we have been experiencing. I hope you get out for a woodland walk to see the many wildflowers in bloom.

Wildflowers, pt.2

I am observing many more wildflowers in the woods this year, with lots of sunlight, cool to warm temperatures, and just enough rainfall for a long spring growing season. Here are a few more species that are blooming now or have foliage up and buds formed and will be open within the next week.

Celandine poppy, Stylophorum diphyllum, is native to southern Illinois woodlands and is considered uncommon in the northern areas of the state. There are historical accounts of this plant being found in the mid-1800s growing along Salt Creek in Bemis Woods. These flowers may be found in backyard gardens. They bloom in late spring for two to three weeks; and this year the weather is extending the bloom period. After blooming, a seed capsule grows, densely covered with soft hairs. The capsule splits open into four segments each containing several seeds.

Celandine poppy,*Stylophorum diphyllum* ,with seed cluster by DonArnold

Celandine poppy foliage is toxic and not eaten by animals, although seeds provide food for woodland mice. Seeds pods contain an oily treat for ants, which distribute the seeds by taking the seed and treat back to their nest. Stems contain a yellowish sap, once used as dye by native Americans. The flower is insect pollinated, although little is known about the insect species that visit. In the absence of insects, flowers are able to self-pollinate.

Jack-in-the-Pulpit, *Arisaema triphyllum* by DonArnold

Jack-in-the-pulpit, Arisaema triphyllum, is a perennial with one or two trifoliate (three-part) leaves. A single whitish-green or reddish-green flower sits on top of a long central stem. The flower consists of a spadix, a fleshly, clublike spike cuddled in a spathe, a leaflike bract the curls around the back and over the top of the spadix. After pollination by gnats or thrips, the spadix develops into a large bunch of fleshy red fruits, each containing one or more seeds. Fruits are eaten by wild turkey and other woodland birds, but the seeds pass through their digestive tracts unharmed and are spread in the woods. All plants are initially male. As they grow, female flowers develop below the male flowers on the spadix. Male flowers die before female flowers mature, preventing self-pollination.

Green Dragon, *Arisaema dracontium* by Doug Grady

Green Dragon fruit bunch, *Arisaema dracontium* by Qwen Wan

The green dragon, Arisaema dracontium, is a less commonly found close relative of jack-in-the-pulpit. This perennial is one to three feet tall with a single, green leaf up to two feet across and divided into five to thirteen leaflets hanging parallel to the ground. An erect, leafless flower stalk about one foot tall ends in a single flower. Like jack-in-the-pulpit, the green dragon flower contains a spadix wrapped by a spathe. The green dragon spathe continues upward to a partially open, pointed top. The spadix has both male and female flowers. After pollination, a large bunch of orange-red berries develops near summer’s end. Green dragon is not as common as jack-in-the-pulpit. Both are found in deciduous woodlands in light shade under trees or along stream banks. Foliage of both plants is mildly toxic and avoided by woodland mammals. The toxicity is from calcium oxylate, a chemical that causes a sensation of being stuck in the mouth and tongue by many small needles.

We usually think of barberry as being an undesirable plant, but one species of this family is Podophyllum peltatum, the mayapple. A perennial with light green to reddish stalks; it may be fertile or infertile. Two petioles, leaf stalks, are found on infertile plants, whereas fertile plants have only one petiole. Flowers on fertile plants are located where the two petioles branch apart. Flowers have six to nine white petals and are light green to pale yellow inside, with yellow anthers. Flower develop into pale yellow, fleshy berries each containing several seeds.

Mayapple, *Podophyllum peltatum* by DonArnold

Mayapple is native to Illinois, occurring mainly in dry, open woodlands. Pollination is by bumblebees and other long-tongued bee species. Foliage is toxic, but berries are edible when ripe and eaten by a variety of woodland amphibians and mammals. Seeds are not digestible and are spread in feces. Plants also spread from rhizotomous roots that can form large, dense colonies. All plant parts contain podophyllotoxin, an ingredient used in many prescription drugs. Historically used by Native Americans for several medicinal purposes including jaundice, constipation , and as a worm expellant, the plant can be toxic to humans if consumed in large quantities.

Some of these woodland wildflowers cover large areas and are easily observed. Get out for a walk in the woods near you to see many of these species blooming throughout the next few weeks. Trees are beginning to leaf out and once the sunlight is blocked off by the canopy, some green foliage will still cover the forest floor, but these wonderful blooms will be gone until next year.

Exotic Invasives

In spring we see a multitude of wildflowers in the woods, but we can also observe the greatest impact of invasive plants. There are sixteen species that are regulated by the Illinois Department of Natural Resources which are illegal to buy, sell, or distribute without a special license. All of these plants present a threat to natural areas and the health of native species.

Woodland habitats are characterized by stands of trees forming a closed canopy that provides a shady forest floor. Native woodland wildflowers compete for sunlight by blooming in early spring before the trees leaf out. Other understory plants are shade-adapted and able to grow in the reduced light under the canopy. Invasive plants grow aggressively and spread outside their native range. Exotic or non-native plants have few issues with disease and the foliage is not eaten by native animals. The combination of these factors make exotic invasive species a serious threat to the sustained health of our native woods. The following three examples are species appearing now in our area woodlands.

Garlic Mustard, *Alliaria petiolata*, by AJC1

Garlic Mustard, *Alliaria petiolata*, S root, by Ellen MacDonald

Garlic mustard, Alliaria petiolata, was imported from Eurasia in the 1800s as a pot herb. It is a biennial, developing flowers and seeds in its second year. Growing 1′-3′ tall, it has medium green leaves with upper stems terminating in a group of small white flowers that bloom for 6-8 weeks in late spring. The taproot has a characteristic “S” shape near the top, but plants are easy to pull out. If the entire root is not pulled out, the plant will quickly send up new shoots. If flowers are mature, seeds will continue to develop and disperse even after the plant is pulled out of the ground and composted. When removal is done in late spring, plants need to be bagged and totally removed from the woodland.

Common buckthorn, *Rhamnus cathartica* by Gail Hampshire

Common buckthorn, Rhamnus cathartica, was imported from Eurasia as a hedge and landscape plant. It develops as a large shrub or small tree, growing to 25′ tall. Buckthorn has glossy leaves and rough textured gray to brown bark covered in white lenticels. If the bark is scratched or peeled away, it is bright yellow underneath. A plant can be either male or female. After flowering, female plants develop dark blue berries, which turn to black by autumn. The berries are eaten by robins, starlings, and other birds, but seeds run through the digestive track undamaged and are thus spread about. Buckthorn releases a chemical called emodin, produced in leaves, berries, bark and roots that exhibits negative effects on other plants in its immediate vicinity. This chemical is toxic to amphibian embryos, disrupting development and preventing successful hatching. Cutting and herbicide application to the stump is an effective treatment.

Amur honeysuckle, *Lonicera Maackii* by Cultivar413

Amur honeysuckle bark, *Lonicera Maackii* by Cathie Bird

Amur honeysuckle, Lonicera maackii, was imported as early as the 1700s from Eurasia as an ornamental species. It is a multi-stemmed shrub, growing up to 20′ tall. Honeysuckle has medium green leaves and gray, woody branches with narrow vertical grooves. Plants bloom in late spring for about 3 weeks, then develop Juicy, bright red berries containing 2-3 seeds each, which are eaten by a variety of songbirds. Honeysuckle is one of the earliest plants to leaf out in spring, effectively preventing other understory plants around it from growing. Cutting the plant down promotes aggressive regrowth, with additional multiple stems and foliage. An herbicide treatment of the stump or foliage is an effective management method.

Control of exotic invasive species is quite difficult. In many cases, cutting simply promotes aggressive regrowth, and studies show that burning does not have much of an impact. The best control methods include preventing establishment of these species or removing the entire plant including the root system. This is not always a practical method. Herbicide has been the next best treatment option, especially in conjunction with cutting before flowers or seeds are produced. Note that the best treatments may be different for each species, so be sure to research different approaches. Several sources of information are available (click on names to link to each) from United States Department of Agriculture, University of Illinois Extension, the Illinois Department of Agriculture, and The Nature Conservancy. Consider the following documents as possible sources to start your research:

From Illinois Invasive Species: Invasive Species of Concern
From Northwest Illinois Forestry Association: Exotic, Invasive Plants in Illinois Habitats
From Northwest Illinois Forestry Association: TNC Weed Control Methods Handbook
From University of Illinois Extension: Illinois Exotic Weed Act

If you have these species in your yard or know of them in the area, consider getting involved in their eradication. Your other plants and animals will be better off.

Wildflowers, pt.1

At this time of year, wildflowers, known as spring ephemerals, take advantage of woodlands where trees have not yet leafed out, and sunlight is able to reach the forest floor. Here are some you may find as you wander the forests of northern Illinois.

Two species of hepatica, both members of the buttercup family, Ranunculaceae. They have simple flowers having an indefinite number of petals, sepals, pistils, and stamens. Each floral part is separate and independently attached to the plant. There is very little consistency in this family, but there is one characteristic that stands out: all species contain an acrid oil that makes each one toxic to some degree. They prefer dappled sunlight in spring and shade in summer and are native to North American woods.

Sharp-lobed hepatica, *Hepatica acutiloba* by Jennifer Anderson hosted by USDA-NRCS Plants database

Round-lobed hepatica, *Hepatica americana* by Bobistraveling

Both sharp-lobed hepatica, Hepatica acutiloba, and round-lobed hepatica, Hepatica americana, have leaves containing three deep lobes and pale blue, pale pink, or white flowers. Plants hybridize easily and are found in early spring. They tend to grow in colonies where groups of flowers persist for two to three weeks, although each individual flower only lasts a few days. No nectar is produced, but pollen is taken by a variety of bees and flies. Chipmunks find the fruit to be one of their favorite foods. Hepatica, meaning ‘of the liver’ in Latin, gets its name from the similarity of the three lobes on each leaf to the shape of a liver.

Spring Beauty, *Claytonia virginica* by Sue OBrien

Spring beauty, Claytonia virginica, has light green foliage surrounding stems terminating in an array of white flowers with varying shades of pink stripes. Flowers bloom in mid to late spring over a 6-8 week period. They open during warm, sunny days but remain closed at night or during cool, overcast periods. Flowers are visited by bees, flies, and butterflies for both pollen and nectar. The corms are often eaten by white-footed mice and Eastern chipmunks. Seed pods nod almost to the ground and contain a small elaiosome, a fleshy structure rich in lipids and proteins attractive to the ant species that are the main dispersers of its seeds.

Spring beauty is commonly found throughout Illinois in open woodlands. Plants can survive stressful conditions and severely degraded areas.

Cutleaf toothwort, *Dentaria laciniata* by DonArnold

Cutleaf toothwort, Dentaria laciniata, has two different types of leaves and a flower stalk ending in a group of small white flowers. Flowers open on warm, sunny days, but remain closed in cooler, overcast conditions. One set of leaves provides food for this year’s flowers and seeds, while a second set of basal leaves stores energy for next year’s shoots. Seed pods develop after the flowers, and will forcefully pop open when touched, shooting seeds in every direction.

A wide variety of bees and early spring butterflies have been observed on the flowers. Forty-eight known species of bees in the Chicago area enjoy its nectar, and two species of leaf beetle use the plant for breeding. There are several species of toothwort in the family, but this is the only one native to Illinois. All are closely related to mustard, broccoli, and cabbage.

White trout lily, *Erythronium albidum* by DonArnold

White trout lily, Erythronium albidum, has green leaves mottled with brown and nodding flowers with six white sepals curved upwards and six yellow stamens hanging downwards. They bloom for about two weeks in mid-spring. After blooming, a three-chambered seed pod grows. Trout lily can reproduce from seeds or from stolons, aboveground shoots that root wherever they touch soil. They can be found everywhere in Illinois except in the farthest northwest corner of the state, near Galena.

There are three native trout lily in Illinois and white trout lily is the most common, but you may also find yellow trout lily, Erythonium americanum, and prairie trout lily, Erythronium mesochoreum. Several bee species are attracted to the pollen and nectar of all three species. Seed pods contain two rows of seed and an attached elaiosome as a treat for the ants who aid in the seed dispersal.

All of these plants can be found in spring in open woodland areas in northern Illinois. Finding large clumps of any of the species is a clear indication of higher quality woodlands that have seen little disturbance over a long period of time. Many wildflower species are being threatened by invasive plants introduced into our woods, and these are all particularly affected by garlic mustard, Alliaria petiolata. In addition, many woodland invasive species leaf out quite early and severely affect the amount of sunlight available for native species growing on forest floors. Come take a walk in one of the many forest preserves and enjoy these flowers among the many that are blooming this spring.

Sharp-lobed hepatica leaves, *Hepatica acutiloba* by Jennifer Anderson hosted by USDA-NRCS Plants database

Winter Tree ID, pt.2

Villages, public parks, and forest preserves in our area contain thousands of trees for our enjoyment. Being able to identify some or all of these can make our walks more fun. In the last blog, I identified several tree characteristics that can be used in tree identification in the winter. Here are some of the more common trees you may find in this area, along with their winter identification characteristics.

Silver Maple bark, by Jerry Jenkins, Forest Atlas Project

Silver Maple flower bud, by Jerry Jenkins, Forest Atlas Project

Silver Maple twig, by Jerry Jenkins, Forest Atlas Project

Silver maple, Acer saccharinum, is a native Illinois tree with bright yellow/green fall leaf colors. When looking at a twig, the terminal and lateral buds will all appear slightly reddish in hue and rounded or pointed. Remember that lateral buds are where new flowers or leaves will grow. If the buds are clustered, this is where flowers will bloom on the twig. The twig is slender and gray to red in color, with buds arranged opposite one another. If you scratch the twig with a fingernail and take a sniff, there is an unpleasant odor. The bark is smooth on young trees, becoming shaggy on older trees.

Hackberry bark, by Jerry Jenkins, Forest Atlas Project

Hackberry twig, by Jerry Jenkins, Forest Atlas Project

The hackberry, Celtis occidentalis, a favorite street tree, is a large, fast growing tree that can reach heights of 40 to 60 feet. Native to Illinois, the hackberry may live for 150 years or more. Twigs in winter lack a terminal bud, but have lateral buds that are brown, flat, and triangular in shape. Lateral buds display an alternate arrangement along very thin twigs. As each new twig grows at a slight angle from the bud, branches take on a zig-zag appearance. The bark, smooth and light gray, is covered with light colored lenticels, and is often times covered with wart-like bumps, their density being greatly variable. Cutting open a twig reveals a banded pith with visible cavities.

White Oak bark, by Jerry Jenkins, Forest Atlas Project

White Oak buds, by Jerry Jenkins, Forest Atlas Project

White oak, Quercus alba, is one of our most popular native hardwood trees. The state tree of Illinois, white oak is used for building dozens of items including cabinets, watertight barrels, floors, caskets, and pianos. In winter, look for bark that is light gray to silver in color. The bark can be quite variable from tight, shallow ridges to broad, loose flaky plating. Many trees exhibiting different bark formation on different parts of the trunk. Twigs display small, rounded, and reddish buds. Lateral buds are alternate on twigs that are slender, smooth and slightly reddish in appearance. Terminal buds are clustered with broad, hairless scales.

Black Walnut leaf scar, by Bruce Kitchoff,c-2015

Black Walnut pith, by Bruce Kitchoff,c-2015

Black walnut, Juglans nigra, is a slow growing tree with a large, shady canopy and rich, dark-brown hardwood. The wood will not warp, can be polished to a high luster, and is highly prized for furniture and veneers. The buds are gray with a light, fuzzy coating of hairs and arranged alternately along the twig. The leaf scars are heart-shaped and contain a very distinct bundle scar that looks like a “monkey face”. The pith is chambered, a distinctive trait found only in black walnut and butternut trees. The bark on this tree is dark brown, with high ridges and deep furrows often arrayed in a diamond-shaped pattern.

Bitternut Hickory bark, by Jerry Jenkins, Forest Atlas Project

Bitternut Hickory buds, by Jerry Jenkins, Forest Atlas Project

Bitternut hickory, Carya cordiformis, also a member of the walnut family, is a medium sized tree, growing 50′-80′ tall with a narrow canopy. This wood burns with an intense heat and is often used for smoking ham, bacon, and other meats due to the distinctive flavor imparted by the smoke. Twigs are thin, shiny, and greenish- to grayish-brown. The alternately arranged buds are bright yellow to sulfur-yellow, covered by two to four large scales that join one another along the edges without overlapping. The bark is light gray, appearing in a diamond-pattern with very shallow ridges.

These trees are some of the most commonly planted in urban communities and found in area forest preserves. All are native to Illinois, are hardy in urban settings, and provide food and shelter for many native wildlife species. Winter identification characteristics are easily visible and a great place to learn how to use a key. Take a walk and get started soon!

Winter Tree ID, pt.1

Many people can identify an oak tree or maple tree during the summer, but how can you ID a tree without leaves? There are several basic characteristics used in tree identification. Many of these are readily visible in winter. When looking at a tree, inspect several of the twigs, the smallest branches on a tree, to rule out any anomalies that may be present on only one. Different characteristics may appear on more than one tree, but when taken all together, a unique combination of traits will identify a single species. As you read the following, a drawing of a twig and all its relevant parts can be referenced at https://mekwamooks.wordpress.com/winter-id/.

The terminal bud, located at the tip of the twig, is where new growth will start from in the spring. Note its size relative to the twig, the bud’s shape, and whether or not it is covered with scales. Buds may be naked, not having any scales, or covered with overlapping scales, or scales may meet at their edges. Lateral buds are arranged along the length of the twig, and they are the site from which a new leaf or flower will grow next year. They will appear on the sides of the twig as you move along it. The arrangement may be opposite, when two buds are at the same point on either side of the twig, or alternate, when a bud on one side is spaced a few inches along the twig from the next bud on the other side.

Lenticels are specialized cells where gas exchange takes place during the growing season. They appear as light or dark spots along the twig. Note the color, size and amount found on a twig, or whether there are none. Running your fingers over the surface of the twig allows you to tell if the lenticels are smooth or rough and raised.

When leaves fall off the tree, they leave behind a leaf scar. Take note of the size and shape of a scar. Is it round, oval, heart-shaped or some other shape? Inside the leaf scar is the bundle scar, where the phloem and xylem layers that transport water and food entered each leaf. The arrangement of the bundle scar in addition to the size and shape of both scars is very helpful in determining the tree species.

The pith inside the twig is another part to use in identification. You will need to break off a twig and slice it lengthwise with a sharp pocketknife to see the center structure of the twig. It can be solid, hollow, spongy or chambered. This structure is found in young branches and is used to store and transport nutrients throughout the plant. As branches mature, storage and transportation will move to the xylem and phloem layers found just underneath the bark.

Peeling bark-Shagbark Hickory, by Jerry Jenkins, Forest Atlas Project

Smooth bark-Musclewood, by Jerry Jenkins, Forest Atlas Project

Warty bark-Hackberry, by Robert H. Mohlenbrock, hosted by the USDA-NRCS PLANTS Database

Bark, another highly visible feature, comes in a variety of colors from gray to tan to dark brown to black. Many species may have a hint of red tones. Identifying the texture of bark is very important. Is it smooth to your touch? Is it covered with warty patches? Some trees have bark that peels off, and it is important to note how the peel starts. Is it the top and bottom ends of each strip that are loose, or the middle that is pulling off to the right or left? Is the bark paper thin and coming off in loosely curled sheets? Thicker bark has a much rougher appearance. Does the bark run in ridges and furrows? Does it appear to be a diamond-shaped pattern on the tree? Some bark looks blocky, with no discernable pattern. Are the blocks flat to the tree or are there deep furrows between the blocks?

Blocky bark-White Oak, by Daniel O. Todd, hosted by the USDA-NRCS PLANTS Database

Furrowed bark-Bur Oak, by W.D. Brush, hosted by the USDA-NRCS PLANTS Database

As you accumulate clues, you can match them against identification guides. A special type of guide, known as a key, will help you identify many of the species found in a given geographic area covered by the key. Keys present a series of questions, each with a limited number of choices to select from. An example is “Winter Tree Finder” by May Theilgaard Watts and Tom Watts, “for identifying deciduous trees in winter.” This book uses a series of questions about twigs to lead the user to a correct identification.

There are many keys and field guides available, but remember to choose ones that pertain to the time of year you are in. Keys for flowers and leaves will not be of great value in winter, and many of the characteristics discussed above, such as scars and buds, will not be available to view in summer. I urge you to get out and try this fun activity before spring.

Publications to get you started:

Winter Tree Finder	May Theilgaard Watts & Tom Watts	Nature Study Guild, 1970
Trees of Illinois	Linda Kershaw	Lone Pine Publishing, 2007
Keys to the Trees of The Chicago Region	Ross C. Clark	The Morton Arboretum, 1988
Bark	Michael Wojtech	University Press of New England, 2011
The Tree Identification Book	George W.D. Symonds	Harper Collins, 1958
Twig Parts Explained	Volunteers @ Me-kwa-mooks Park, Seattle	https://mekwamooks.wordpress.com/winter-id/

Sap & Syrup

With cold winter mornings becoming the routine, hot breakfasts are welcome in our household. Pancakes, waffles and french toast all have at least one common ingredient – maple syrup. Most varieties of syrup come from maple trees. Sycamore, walnut, butternut, basswood, birch, and hickory trees also produce syrup.

Maple syrup is unique to North America and is one of the oldest known crops, first made by the indigenous peoples in this region, although exactly when and how it was discovered remains a mystery. Sap from sugar maple, Acer saccharum, red maple, Acer rubrum, or black maple, Acer nigrum, is used in the production of maple syrup. A maple tree needs to be about 12″ in diameter at breast height, or about 40 years old, to produce enough sap to be economically viable for syrup production. Sap from a tree is between 0.5% and 10% sugar. Syrup, a product created by processing the sap, must contain a minimum sugar content of 66.7% to be sold commercially. A single tap that yields 10 gallons of sap is enough to make about one quart of syrup. Raw sap has little or no taste. Through the process of boiling off the water content, sugar, in the form of sucrose, is concentrated as the mixture thickens. The unique flavor of each variety comes from the mixture of concentrated sugar and nitrogenous chemicals present in the sap.

Sap must flow out of the tree in order to collect it. Trees have two layers of cells to transport food and water: the phloem and the xylem. Immediately under the bark, the phloem transports food for the tree in both directions, up and down. The xylem, an inner layer, transports water up the tree through a series of tubes and cell chambers. In the transpiration process, special cells called stomata, located on the undersides of leaves, open to take in carbon dioxide during photosynthesis. At the same time, water is lost by evaporation to the outside air. This creates negative tension in the xylem moving water by pulling it up to each leaf. Another factor affecting the xylem is root pressure, created by accumulating minerals in rain water in the soil. This results in positive tension on the water in the soil and pushes water into roots and xylem. In winter, when there are no leaves and no rain, neither of these processes are active.

Tap and Bucket on Sugar Maple, by Nicolas Longchamps, 2008

While sap flow in winter is still not fully understood, we know that it requires temperatures to cycle between nighttime freezing and daytime thawing. In sap-producing trees, the cell chambers in the xylem contain various gases and the tubes between the cells contain sap (i.e. water plus nutrients). As temperatures drop at night, some of the gas is absorbed by the sap creating empty space that acts as a vacuum to pull in more water from soil below the freeze line. As temperatures continue to drop below freezing, sap turns to ice, increasing in volume and trapping the remaining gases under pressure in each cell chamber. During the day, as temperatures inside the tree rise above freezing, the ice melts and the pressurized gases push the sap out any opening in the tree.

Understanding the physiological cycles of each tree species is vital to obtaining good sap production without causing harm. Tapping is not pruning, and no pruning should be done to “bleeder” trees until early summer. Individual trees that are widely spaced and have better access to the sun during the growing season produce higher sugar content. Sap flow is highly dependent on late winter / early spring weather. Water must be available to tree roots and temperatures must cycle daily between freezing and thawing. To make syrup, a higher sugar content requires less processing, and the right combination of nutrients will produce great taste. I hope you all get a chance to enjoy the many flavors of this unique food.

For more information on how to tap without damaging the tree, click on: DaveyTreeBlog

Conifers

Conifers are one member of a group of plants known as gymnosperms, meaning ‘naked seeds’, a reference to the seed not being enclosed in an ovary or fruit. These plants do not flower, but have both male and female cones. The male cones carry pollen, which is dispersed by the wind. The female cones that come in contact with the blowing pollen will take some into the ova and produce seeds in the cone. Cones are green as they grow, turning brown as the seeds mature. When cones open, seeds are dispersed by falling to the ground or being picked up and moved by animals. In some conifer species, cones will not open until certain environmental conditions are met, namely the presence of fire. These species have serotinous cones, ones that only open when exposed to high heat. Fire also kills other plants that compete with conifers for resources such as sunlight and water, and it releases minerals from burned plants into the soil providing nutrients for new conifer seedlings.

White Spruce, *Picea glauca*, by Northern Forest Atlas Foundation

Most conifers are evergreen, although a few are deciduous. Deciduous trees lose their leaves all at the same time, when temperatures start to drop in autumn. Evergreens also lose their needles, a few at a time throughout the year, and they are quickly replaced by new growth so the tree is never bare. Evergreen needles are thin leaves found on several types of conifer including fir, spruce, and pine. Other types of conifers like juniper, cypress and cedar, have soft, scale-like needles. An examination of the needles is the best way to identify a conifer species. Whether they are stiff and sharp, or flexible and soft; bunched in groups or growing singly; and the number of needles that are in each bundle will help you to identify a specific tree species.

Austrian Pine, *Pinus nigra*, needles in sheathed pairs, by DonArnold

Climate conditions, especially temperature and precipitation, greatly influence the tree species found in any one area. Colder temperatures reduce the ability of plants to function. Deciduous plants handle this change by entering a state of dormancy until warmer temperatures arrive in spring. Precipitation in northern Illinois is generally well distributed throughout the year, although in winter, it falls as snow. Combined with a frozen soil layer, this water is not available for ready use by any plant species until the spring thaw. Evergreen species are well equipped to handle these conditions. Needles have a waxy, outer covering, while roots and stems are filled with resin, a chemical that acts as antifreeze. The general shape of the tree, with branches sloping down and out, keeps snow from accumulating and freezing on the foliage. The plants can survive very cold temperatures without damage and are able to start photosynthesizing food as soon as liquid water is available in spring. This gives evergreen species a jump on shorter growing seasons in cooler northern climates.

Austrian Pine, *Pinus nigra*, unopened seed cone, by DonArnold

Conifers in this area are used extensively by birds, mammals and insects for food and shelter. They make good habitat, providing protection from wind, rain and flying predators. A wide variety of insects call conifers home including spider mites, aphids, bark beetles and various caterpillars. Many of these insect species provide food for woodpeckers and nuthatches. Squirrel nests are well screened from wind and precipitation by evergreen boughs. During the day, many bird species like to browse among the ground litter of pine needles and fallen food. And later in the evening, that same activity is taken up by several mammals prowling the night time.

Hairy Woodpecker searching for insects on Austrian Pine, by DonArnold

There are about 700 conifer species found world-wide, and they can be found in backyards, city parks and nature areas all over DuPage County. They are most abundant in cooler climates and are important timber trees. All are softwoods, a versatile building material for mouldings, windows, flooring, paneling and plywood. They provide great backyard habitat in our area, and serve as an important natural resource for many over-wintering species in DuPage County.

Autumn Leaves

Autumn officially began just a few short weeks ago, but we are already able to observe the changing colors and leaf fall in the woods. There is much about nature that we can appreciate at this time of year, with observation and a little help from books, blogs and research.

Hackberry, *Celtis occidentalis* by DonArnold

Leaves on trees produce food for the rest of the tree. They do this by a process called photosynthesis which combines carbon dioxide, water, pigments and energy to create sugars and oxygen. The sugars are used to feed the rest of the tree. The oxygen is a by-product that is released into the surrounding atmosphere. The various pigments include chlorophylls, which allow a plant to absorb energy from light; carotenoids, which also assist in energy absorption; and xanthophylls, which protect the photosynthesis process from the toxic elements of light. All of these pigments give leaves certain colors. During spring and summer, chlorophylls are present in the highest concentrations, and they give leaves their green color. In autumn and winter, as the number of hours of light per day gets shorter, the photosynthesis process slows down and finally ceases. The amount of chlorophyll decreases and color from the other pigments starts to show through. Carotenoids are orange and yellow, while xanthophylls are yellow and brown. Another pigment that is only present when there is more sugar being produced than used by the plant is anthocyanin, and it colors the leaves red and purple.

Colors in autumn may be brilliant in some years, or more muted in other years. This intensity is determined by the weather conditions during late summer and autumn. Carotenoids and xanthophylls are always present in the leaves during food production season. Dry periods in late summer reduce the amount of sugar being produced. Thus, the red and purple hues from anthocyanin may be muted or not present at all, allowing more of the orange, yellow, and brown pigments to be displayed. Colors may be more muted with less moisture in the leaves and the length of time the leaves remain on the tree may be shortened.

White Ash, *Fraxinus americana*, by DonArnold

Color is also affected by temperature. When days are warm and sunny, leaves produce a lot of sugar. At night, in cooler weather, leaf veins constrict and limit the amount of sugar flowing to the rest of the plant, thus creating an excess of sugar remaining in the leaves each day. This is when we see lots of red and purple hues from anthocyanins displayed.

While leaves are falling, trees are preparing for spring in other ways. During senescence, that time of year when leaves grow old, carbohydrates, nitrogen, sulfur, phosphorous and potassium are reabsorbed by the tree in great quantities from the leaves. None of these elements are lost, but they are stored in twig, stem and root tissues. They will be used in springtime to fuel the beginning of the next year’s growth.

Another way for a tree to get a head start on next year comes from bud growth. Buds are formed in late summer or early fall, and are covered with modified leaves called bud scales. These will seal them against the cold and wet weather of winter. Most of the buds that you can observe are leaf buds containing tightly packed, immature leaves. In spring, when the weather gets warm enough for sap to start flowing, these buds will unfold into the first leaves of spring. Larger size buds may be flower buds, depending on the species and age of the tree. Flower buds do not change much in the winter months, but they will grow a bit larger as we get near bud burst in spring. You may also observe terminal buds, found at the ends of branches. Oak trees, as well as other species, add length to existing branches when these buds begin their spring growth.

There are numerous good field guides about trees available, but I would like to mention four that I use. “Winter Tree Finder” by May Thielgaard Watts and Tom Watts instructs you in how to look at a twig and its structures. Then the book guides you through an examination of a twig to identify the genus and species of deciduous trees in winter. “Trees of Illinois” by Linda Kershaw is another book organized using keys with excellent pictures of leaves, buds and fruit for each species, along with ranges and characteristics of each. “The Tree Identification Book” by George W.D. Symonds provides a wide variety of black and white photographs for every part of a tree including thorns, leaves, flowers, fruit, twigs, buds, bark and needles. Peterson Field Guides presents “Ecology of Eastern Forests,” with chapters describing the plants and animals encountered in different types of forests, and how they all function together. Other chapters talk about how forest patterns change with the various seasons.

Pumpkins

We are quickly approaching two of my favorite holidays, and they both involve pumpkins! Everyone knows something about pumpkins from their bright orange color to their unique taste. Let’s go further and explore some of the many ways this wonderful fruit has impacted our culture.

Pumpkins are a fruit from various species of winter squash, all from the genus Cucurbita. The type of fruit is called ‘pepo’, which is from the Greek word ‘pepon’ meaning a large melon. Pumpkins are native to northeastern Mexico and the southern United States. Pumpkins are one of the oldest domesticated plants, found as early as 7500 B.C. They are grown on every continent except Antarctica, and they are widely used throughout the world for food, aesthetic and recreational purposes. About half of the world’s crop is grown in China and India. The U.S. grows about 2.2 billion pounds of pumpkins each year, comprising less than 4% of the world’s production.

Pumpkins should be planted in late May in our area. Plants produce both male and female flowers. Flowers can be fertilized by a wide range of pollinator insects, but historically the plants attract the native squash bee, Peponapis pruinoso or the Eastern bumblebee, Bombus impatiens. Pollen grains from the plants in this genus are quite large, and can be managed by only a handful of species. With the decline in the population of squash bees in the U.S., commercial production will use captive honeybees or hand pollination if there are not enough wild bees in an area.

Pumpkins are classified as fruit, the seed bearing structure of a flowering plant. As they start to grow, they are green and will turn to orange for the same reason green leaves on deciduous trees change to fall colors. As the amount of daylight begins to decrease in the autumn, chlorophyll production slows and then ceases. The remaining carotenoids in the skin of the fruit are orange or red or yellow in color and are fully revealed after no more chlorophyll is left. There are also pumpkin cultivars that have been grown to display other colors including white, red, yellow, green, and blue. Cultivars with larger sized fruit generally produce 1-2 pumpkins per plant, medium sized fruit plants produce 3-6 pumpkins each and small sized fruit plants may produce 10-12 per plant.

The largest growing sites in the U.S. are found in Illinois, Indiana, Ohio, Pennsylvania and California. Illinois produces about 95% of the commercially available pumpkin products in the United States with Nestle’s Morton, Illinois, production plant selling 85% of all pumpkin products under the trade name Libby. Edible parts of the plants include the shell, seeds, leaves and flowers. Pumpkins can be boiled, steamed or roasted, and are most often mashed. Popular pumpkin products include pie filling, spice pumpkin products and seeds, but are also used as dietary supplements by veterinarians, most often fed to poultry in the winter to help maintain egg production. The original pumpkin pie cooked by colonists consisted of slicing off the top of the pumpkin, scooping out all of the seeds, filling the shell with milk, spices and honey, and cooking it for several hours in hot coals.

While pumpkins are a delicious food, they are also used in a variety of other ways. “Punkin Chunkin” has been a competitive sport for many years and involves building a device to throw a pumpkin the farthest. The Guinness world record is held by “Big 10 inch,” a pneumatic cannon that launched a pumpkin 5,545 feet in 2010 in Moab, Utah. Note that pumpkins that burst in flight are disqualified.

Pumpkin festivals celebrating those who can grow the largest pumpkins are also popular all across the United States. There will be four competition sites in Illinois this year and you can find all the information at Pumpkin Festivals. Growers of giant pumpkins have been competing since at least the early 1960’s, and in 1979 in Philadelphia, a Nova Scotia farmer named Howard Dill won with a 438 pounder. In 2012, the first 1-ton plus pumpkin won the Topsfield, Massachusetts weigh off at 2,009 pounds, grown by Ron Wallace of Greene, RI. In 2019, the winner was an impressive 2,517 pounds grown by Karl and Beverly Haist in New York. Don’t plan to enter unless you can top at least the one-ton mark; nothing less will be considered by most festivals this year!

Literature is another place we find many references to pumpkins. Charles Perrault, a French author, published “Tales and Stories of the Past With Morals” in 1697. Among the many stories in the work was “Cinderella,” a folk tale about undeserved oppression and reward. Invited to the royal ball, her fairy godmother provides Cinderella with the means to get there by turning a pumpkin into a beautiful coach. Another work, “The Legend of Sleepy Hollow’, published by Washington Irving in 1820, tells the story of Ichabod Crane being attacked on Halloween night by the Headless Horseman who carries a pumpkin, his head, possibly, on his saddle. And we have all enjoyed waiting for the Great Pumpkin with Linus each year on Halloween night. As Linus tells us in “It’s the Great Pumpkin, Charlie Brown,” “On Halloween night, the Great Pumpkin rises out of his pumpkin patch and flies through the air with his bag of toys for all the children!”

Jack-o-lanterns are an autumn tradition dating far back into British and Irish history. Their origin comes from an Irish tale about Stingy Jack, who invited the devil for a drink. But Jack did not want to pay for the drinks, so he convinced the Devil to change into a coin, to be used for pay. After changing, Jack decided not to use that coin, but to put it into his pocket next to a silver cross that prevented the devil from changing back. Jack finally freed the devil under the condition that the devil would not bother him nor would he claim Jack’s soul when Jack died. Soon after, Jack did die, and God would not let him into heaven because of his unsavory ways and the Devil would not let Jack into hell because of their agreement. Jack was forced to forever wander the dark night, using a carved out turnip with a bright coal to light his way. He was referred to as “Jack of the Lantern”, soon shortened to Jack O’Lantern. People would carve scary faces into turnips and large beets to place in their windows to frighten away Stingy Jack’s ghost. Carried over to the U.S. by colonists, pumpkins were found to make great Jack O’Lanterns. They are still used today to scare away the evil spirits that roam the autumn nights.

The Itch!!

Over the past few months, like many other people, I have been out hiking in the area Forest Preserves and natural sites. Each time I go out, I try to think about getting properly prepared before heading out the door. Will I be hiking off the trail through long grass? Will I need long pants, long sleeves or a hat? How about deterring mosquitoes? Are they out now and should I be taking along protection? Here are some simple precautions to make your hike a great experience.

Poison Ivy vine, Toxicodendron radicans by Kerry Wixted

Poison Ivy, Toxicodendron radicans by Janet Tarbox

If you are a steward or wildlife monitor, you may well be hiking off the trail and into areas where the plants are not easy to see, identify, or walk around. And even if you are just out for a nice hike on the trail, species growing along the edges may be ones that you want to be sure to avoid. Poison Ivy,Toxicodendron radicans, is one of the best known plants found everywhere in northern Illinois that causes itching, a rash or swelling. The plant is commonly found in woodlands and savannas, but can also be found in dry meadows or along prairie edges. It grows as a small shrub or as a woody vine, wrapping around tree trunks and climbing to great heights. The leaves are distinctive: they grow in groups of three and have smooth edges, often with a thumb on the two side leaves. Vines growing up trees are thick and hairy, with many small tendrils reaching out to anchor the plant to a trunk or limb. Every part of the plant contains an oil that may cause a rash or itching when touched. It is easy to brush a plant and have the oil cling to a shoe or cloth surfaces, which can be a further problem if not washed out. If you get the oil on your skin or clothes, wash with cool water and soap, or consider using Tecnu Original Outdoor Skin Cleanser, a specialty line of products, to remove the oil.

Wild Parsnip, Pastinaca sativa by John W.

Wild Parsnip, Pastinaca sativa, a species introduced from Europe and commonly found in prairies, vacant lots, roadsides, woodland edges and along railroad tracks is another plant to watch for and avoid. The flowers are arrayed in a slightly curved umbel at the end of tall stems, showing bright yellow petals, sometimes mistaken for Golden Alexanders which bloom earlier in spring. The plant can grow from two to five feet high. All parts of the plant contain a UV-phototoxic juice that will transfer easily to skin or clothes if the plant is brushed against. This juice can cause a burn-like rash that is severely multiplied in effect when exposed to direct sunlight. A burn may also appear on cloudy days from ultraviolet wavelength light present even through cloud cover. Any exposure should be treated as a possible serious burn, and you should seek medical assistance.

American Dog Tick, Dermacentor variabilis by Roy Cohutta

Animals may also cause problems. Ticks, along with spiders and mites, are members of the class Arachnida. These animals feed on mammals, birds and reptiles. Ticks perch on foliage between ground level and about four feet high and wait for an animal to brush against them. They leave their perches and find a suitable spot to latch onto their host using a hook-like appendage located below their mouth. After a blood meal, the engorged tick will simply drop off to the ground. However, they can carry diseases harmful to humans.

Gulf Coast Tick, Amblyomma maculatum by Roy Cohutta

Lone Star Tick, Amblyomma americanum by mossdude

Black-Legged Tick, Ixodes scapularis by Lynette Elliot

There are four common tick species in our area including the American Dog Tick, sometimes referred to as the wood tick, the Lone Star Tick, the black-legged tick, also known as the deer tick, and the Gulf Coast tick. Wood ticks are generally harmless to humans; deer ticks may carry Lyme Disease; the Lone Star Tick may carry Rocky Mountain Spotted Fever; and the Gulf Coast Tick, new to this area within the past 18 months, may carry Tidewater Spotted Fever.

Eastern Yellow Jacket by Lynette Elliott

The Eastern Yellow Jacket, Vespula maculifrons, is an insect that comes out in the heat of late summer. Yellow Jackets are social wasps that live together in one hive. In spring, a single mated female, called a queen, builds a nest at ground level or possibly in a fallen stump or log. She will tend the larvae until the first brood of adults, all sterile females, emerge. The adults take over all nest maintenance while the queen continues to lay eggs. In autumn, eggs for new queens are laid, as well as unfertilized male eggs. New queens and males emerge in late autumn, mate and the new queens seek shelter for the winter in litter or soil. With the arrival of winter, the remaining colony dies.

All wasps are predatory and keep populations of smaller species, such as mites and aphids, under control in our gardens. While these insects are predatory, they are also attracted by any sweet odor and can be pests for outdoor dining. The females can sting and be very aggressive when trying to nab food from your picnic. If they are threatened, especially if a nest is found and agitated, they will swarm, stinging repeatedly and may give chase for long distances.

Inland Floodwater Mosquito, Aedes vexans by Robert Lord Zimlich

The mosquito, one of our least favorite insects, is best known for the biting females, which must have a blood meal in order to develop eggs. Males do not bite, but feed on plant juices. Mosquitos are considered one of the most harmful insects to humans because of the many diseases they may carry. Also dangerous to canines, mosquitos are the primary cause of heartworm disease. There are several different species of mosquito found in Illinois, active during a wide range of day and night hours. Most of the bites in northern Illinois cause an itching sensation that can last for several days; however, they may also be vectors for West Nile Virus. Best practices to avoid being bitten include wearing light colored clothes, using an insect repellant when outside, and removing any standing water from your yard. There are several good websites including Illinois EPA for Mosquito Control.

Pollinator Garden

Our pollinator garden is filling in rapidly with the warmer temperatures and ample amounts of rain we are experiencing. Many species in our area, including bees, wasps, flies, ants and hummingbirds are pollinators providing plant species with the essential service of moving pollen from one flower to another for fertilization. Many popular native species are found in our garden; let’s take a look at a few of the ones now in bloom.

Golden Alexanders, *Zizia aurea* by DonArnold

Mining Bee on Golden Alexander, © Heather Holm, 2015.

Golden Alexanders, Zizia aurea, is found in a variety of natural environments from open woodlands to prairies to fens. This member of the parsley family is visited by Pearl Crescent butterflies, Phyciodes tharos, and Spotted Thyris moths, Thyris maculata, especially where these insects find other food species including Clematis and Houstonia. Mining bees, small in size and emerging in early spring, are the primary pollinator, picking up pollen on the hairs of their upper legs as they feed on the flowers.

Virginia Waterleaf, *Hydrophyllum virginiatum* by DonArnold

Another favorite pollen source for bees is Virginia Waterleaf, Hydrophyllum virginianum. With its white to pale violet flowers and leaves that look like they are stained from water; this plant’s nectar also attracts the Red Admiral butterfly, Vanessa atalanta, and a few species of beetles. The stamens on this flower extend well past the petals making it difficult for small, short-tongued insects to get close enough to the flower tube to obtain nectar. Bumble bees, one of the primary pollinators feeding on the nectar, use their larger bodies to push past the stamens picking up pollen to transfer from one flower to another.

Woodland phlox, *Phlox divaricata* by Joshua Mayer, 2010

Woodland Phlox, Phlox divaricata, also known as Wild Blue Phlox, is often found in open woodlands. This flower is attractive for pollinator gardens due to its blue flowers and good growth in partially shaded areas. Pollinators include many butterfly and moth species with long tongues that can reach deep into the long flower tube for the nectar at the base. As the butterfly feeds, its proboscis (tongue) contacts the stamens to pick up pollen which is transferred to the next flower.

Jacob’s Ladder, *Ploemonium reptans* by DonArnold

Another flower in the blue spectrum is Jacob’s Ladder, Polemonium reptans. This species does well in partial shade or a moist area in full sun. The flowers are visited by bees, flies and beetles. Large bees are the best pollinators as they collect pollen on their heads and thoraxes when pushing through the stamens to get to the nectar at the base of the petals. Previously collected pollen brushes off on subsequently visited flowers.

Spring Wildflowers

We may not be able to tell exactly when winter ends and spring begins, but the plant community all around us has determined that the change has already happened for this year. With the longer days and warming weather comes myriad changes in the plant community. This is the chance for us to observe many species that come and go very quickly at this time of year. These are the wildflowers of spring, and a few early ones to look for on your walks are listed below.

*Dodecatheon meadia*, Shooting Star by Sue

One of the more showy flowers is Shooting Star, Dodecatheon meadia. A delicate pink, lilac or white bloom droops from a single tall stalk in the middle of a grouping of lance-shaped leaves. The plant may stand from 6″ to 20″ high. The flowers form a cone surrounding the stalk with lobes bent backwards. This plant is pollinated by female bumble bees that collect the yellow powder-like pollen by vibrating the anthers with two or three short sonic bursts called buzz-pollination. The place to observe all this activity includes brightly lit open woods and meadows.

Virginia Bluebells, *Mertensia virginica* by Sue

Virginia Bluebells, Mertensia virginica, may not be in full bloom, yet, but will soon be spectacular in their showiness. They are found in rich, damp woodlands, many times along streams and rivers. In many areas, they can be found growing in great swaths covering large areas of the forest floor in open woodlands. Trumpet shaped flowers nodding from a long stalk are about an inch long, pink when young but turning to a beautiful, rich hue of blue.

Dutchmans Breeches, *Dicentra cucullaria* by Sue

Dutchman’s Breeches, Dicentra cucullaria, is a common species found in open, dry woodlands. The flower, in white or pink, appears as if someone is hanging out their trousers to dry. The green base of the plant is located far below the naked flower stalk and is composed of several fern like leaves. This flower is mainly pollinated by bumblebees, who have a longer proboscis than honey bees, allowing them to tap the flower for its nectar.

Bloodroot, *Sanguinaria canadensis* by Sue

Another showy but short-lived bloom in the woods at this time is Bloodroot, Sanguinaria canadensis, found in dry woodland areas. Sanguine, an adjective for the color of blood, appropriately describes the juice derived from the plant. A single leaf divided into five to nine deep round lobes clasps the flower stalk, wrapping around the base. A single white flower rises 3″-6″ above the leaf. The flowers contain no nectar, but attract a variety of female bees as well as the false blister beetle to collect pollen.