May 2021 – Discover-Nature

Neighborhood Nests

There is a lot of activity taking place outdoors. We are a couple of months into spring, and many birds have returned to warm weather activities after winter. They are actively engaged in finding mates, building nests, laying eggs, and raising young. Birds in backyards, woodlands and open fields build a variety of types of nests, many of which we can find when we are outside enjoying our daily activities.

Nests are used by birds of all species as a place where eggs can be kept warm and safe until they are ready to hatch. Some birds build a new nest every year, and some will build a nest for every new clutch of eggs. Others return to use an old nest, one of their own they keep adding material to or one that is found in a convenient place worthy of renovation and reuse.

The type of nest and the habitat it is located in are excellent indicators of the specific bird living there. Each species is known for a specific type of construction including ground nests, platforms located low in foliage or high in trees, open cup nests, closed or domed cup nests, and nests created using a natural cavity, such as a tree hollow. Nests keep eggs and young together, provide a place hidden from predators, with protection from harsh weather. They are built from materials available in the area. These materials include twigs to pine needles to monofilament fishing line. The form and function of the nest does not widely vary for any species. As you are out walking this spring, here are a few of the more interesting nests that you may be able to spot.

Blue jays, Cyanocitta cristata, are found in forests, meadows, parks and backyards, and build a bulky nest of thorny twigs, bark, moss and string. Their nests are located in the crotch or outer branch of deciduous or conifer trees. Nests are well hidden, seven to eight inches across, and lined with soft rootlets. Jays, known for their brash, loud calls, exhibit very different behavior around nest sites, becoming very quiet so as to not give away the nest location.

Ruby-throated Hummingbird on nest by Lorie Shaull

Ruby-throated hummingbirds, Archilochus colubris, are small, very quick fliers. Nests can be found in a variety of trees, ten to twenty feet off the ground. Made of plant down, fibers, and bud scales, nests are attached to a twig or small branch that slants downward. Hummingbirds use spider silk to securely bind the nest to the limb under a canopy of leaves. The nest, about the size of a thimble and covered with green-blue lichen, is very hard to see, resembling a knot on the branch.

The Baltimore oriole, Icterus galbula, is often found in city parks and backyards. The oriole builds a thin-walled, deep, basket-like nest of coarse grass lined with finer grass. The nest hangs from a forked tree branch between ten and twenty feet off the ground. Nests are commonly hung in locations that are well concealed by leaves. Many orioles like to nest with Eastern kingbirds, an aggressive species that keeps away predators and cowbirds.

As you are out walking along stream banks and woodland paths, and maintaining a close watch on your own backyard, keep a keen eye open for observing the places that birds call home. Getting to know the area and habits of the birds as they raise families is a rewarding experience.

A Drought of Amphibians

This year we are experiencing drought conditions in northeast Illinois. A drought, defined as a period of little or no rain, can have major impacts on the amphibian populations of an area. At the end of winter, as snow melts and expected spring rainstorms move into the area, many ephemeral wetlands fill with water. These pools, marshes and ponds contain water for only short periods ranging from several weeks to a few months. But they are an important link in the chain of amphibian reproduction.

Many frogs and toads live in woodland areas, but depend on wetlands for breeding and habitat for their young. Male frogs and toads return to local ponds each spring to find a mate by calling. Most calling is done in the evening, but sometimes individuals call during the day. Females will find their way to their favorite singer, then lay a gelatinous egg sac, which the male fertilizes. Eggs may be located on floating vegetation, hanging under rocks or logs, or laid on the bottom. Eggs have no shell and must remain wet to live. Eggs hatch into tadpoles in a week or less. Tadpoles may transform to adult form in as little as two weeks or as long as the following year.

Wetlands of all types are showing changes due to the drought conditions. Shallow ponds and marsh areas are dry or retaining only enough moisture to have wet soil, and are no longer a usable wetland for many species. Deeper ponds are down several inches in depth. A difference of only a few inches in depth can add several feet of shoreline where banks gradually slope into the water. Exposed rocks and logs used by turtles for basking are high enough over the water’s surface that they may no longer be accessible to these species. Creeks and rivers are lower and slower. Turtles and water snakes that depend on depth and fast flow for protection may find these are no longer a means of escape.

Shrinking permanent wetlands put pressure on the species that already live there. Ponds are habitat for newts, tadpoles, crustaceans, frogs, toads, turtles, birds, naiads and insects, and microscopic life. As the amount of water decreases, habitat in the pond is reduced. Shallows where a bank slowly submerges may have a steeper drop-off. Logs once laying at surface level may be several inches higher than the surface, eliminating areas underneath, once used for protection. Less water means less available oxygen and food for the animals already sharing the pool. Den and nest sites in banks at the water’s edge become more exposed.

Rain during the early part of May has helped alleviate some of these issues, but more rain is needed, continuing into the summer. Maintaining your own backyard wet areas with shade and consistent watering provides good habitat for many animals that live among us. You can watch many of these species in area wetlands on trails and in local parks this spring.

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.