Final Visit to Thomas Woods

 Field Observations

    

    As I walked around the wetland to my habitat, I noticed as I approached Thomas Woods that the patch of Rosinweed was much taller than me now. The mosquitoes have also made a pesky return, and they buzz around my ears, making me regret not applying some bug spray before my walk today.         

    However, I do not regret coming out here this afternoon, as I enjoy the shade of my trees preventing the late afternoon sun from blinding me as I look up at the tree tops, trying to see the shape of leaves of trees I wish to try to identify. I also look down at the ground as well, to see if there are any new plants flowering, and low and behold I see a new yellow flower that I have not previously seen this summer. Growing at the edge of the woods, the little sunflower turns out to be a Woodland Sunflower, at least that is where I ended up at in Newcomb's Wildflower Guide. I have grown more confident in my use of this field guide book and I use it more on my walks than at the beginning of classes in July. While I'm kneeling on the ground following the flower dichotomous key, a tiny bird perches in the tree above me, seeming to barely take a breath inbetween its warning call about me. I tried to identify the species but I could not see much other than it was very tiny and had a small patch of white on the throat or underbelly. I did not hear any other birds which was unusual. 

    My last visit to Thomas Woods for the purpose of this blog ended with a very quiet walk through the woods, with only the buzz of mosquitoes following me as an entourage. As I walk, I think about how I am determined to return here in later fall and winter to continue my learning. 

Species Identification

White Oak (Quercus alba)

    

    White Oaks are a large tree, often growing up to 50-80 feet tall, which has wide-spreading branches that extend horizontally in the canopy. In the fall, their leaves are a red-wine color. These trees are native to Northern America, especially the Illinois-Indiana regions. They are shade-intolerant trees, and require access to full sunlight to grow. White Oaks prefer moist, well drained soils but they are drought tolerant as well during dryer years. You can recognize a White Oak by their gray or light tannish bark that has thick overlapping plates or thick ridges. Sometimes parts of the bark can be smooth due to smooth patch fungus which is harmless to the tree.  White Oak leaves have rounded leaf margins. Their nuts are about 1 inch long and have a warty cap on top. These acorns will ripen and fall to the ground in the fall. Because these trees have a slow, moderate growth rate, White Oaks can live for a very long time. Oak trees provide habitat for birds and their acorns provide food for many animal species. 

The Morton Arboretum. (2020). White oak. https://www.mortonarb.org/trees-plants/tree-plant-descriptions/white-oak

Sugar Maple (Acer saccharum)

    Sugar Maple, also known as Hard Maple or Rock Maple, is a Midwestern tree loved for the maple syrup that can be harvested from them and the beautiful yellow to burnt orange leaves that appear in the fall. These tall trees, often getting above 40 feet tall, prefer access to lots of sunlight although they do well in partial shade as well, and live on moist, well drained soils. Sugar Maples are tolerant of acidic soils but intolerant of drought. Sugar Maples are also intolerant of salty soils and poor drainage. These trees have deeply furrowed, gray-brown bark. Their leaves are a dark shade of green in the summer months, and have 5 lobes. The 3-6 inch leaves are simple and occur in opposite pairs on the branches. When flowering, Sugar Maples have tiny, pale yellow flowers and the fruits are 1 inch long paired, winged seeds. Maple trees provide habitat for birds, insects, and mammals. 

The Morton Arboretum. (2020). Sugar maple. https://www.mortonarb.org/trees-plants/tree-plant-descriptions/sugar-maple 

Woodland Sunflower (Helianthus divaricatus)

    Woodland Sunflower is a perennial herbaceous plant that typically grows 2.5 to 6 feet tall. The flowers occur on the branches that come off a green or dark purple, slender, central stem. The stem has short, stiff hairs on it. The leaves of this sunflower are opposite with very short petioles, and are between 2-6 inches long. A very distinctive feature of this plant is that each pair of opposite leaves is rotated 90 degrees from the pair of leaves below it. The leaves can also be toothed as well but they are not always. Woodland Sunflower leaves are yellowish green or a medium green and paler below, and they are hairy as well. The flowers are yellow, with 1.5 to 3 inch wide flowerheads and have between 8-15 petals. Woodland Sunflowers prefer full or partial sunlight and live on moist to dry-mesic soils. Habitats include upland rocky woodlands, sandy woodlands, upland savannas, sandy savannas, woodland borders, hill prairies, and moist or dry-mesic prairies. They do especially well where wildfires occur as this reduces their competition with other woody vegetation. Woodland Sunflowers have lots of specialist pollinators, mainly various native bee species. Butterflies, flies, and wasps are also pollinators as well. They are also the host plants for many caterpillars, such as Painted Lady, Silvery Checkerspot, Gorgon Checkerspot, Banded Sunflower Moth, etc. Many other insects eat the leaves as well, and many bird species, such as Goldfinch and Tufted Titmouse, eat the seeds of Woodland Sunflowers.  

 Hilty, John. (2020). Helianthus divaricatus. Illinois Wildflowers. https://www.illinoiswildflowers.info/savanna/plants/wd_sunflower.html

Tiger Swallowtail (Papilio glaucus)

    Eastern Tiger Swallowtail, or Tiger Swallowtail for short, is a butterfly that lives from the Great Plains out to New England and the southern Great Lake States down to Texas and Florida. Adults of this species are pretty large, their wingspread is 3-5.5 inches, and are typically yellow with four black bands on the top of their wings although some females are black instead of yellow. Their wing margins are black with yellow spots and then on the bottom of the hindwing are blue spots along the edge. An interesting bit of biology about this species is that their sex chromosomes are the opposite when compared to mammals. Female Swallowtails have XY chromosomes and males have XX. Yellow females will lay eggs that will grow into yellow females and dark females lay eggs that will become dark females, which means the gene for color is on their Y chromosomes. 

    The caterpillars go through 5 instars before cocooning. The first three caterpillar stages are dark brown, white saddle marking, and look like bird poop. The fourth and fifth instars are then green, with swollen thorax and light blue dots on each abdominal segment. Each larvae also has eyespots on their thorax as well to make them look scary to potential predators. The eyespots are a black ring encircling yellow which has a smaller blue spot. Tiger Swallowtail caterpillar host plants include white ash, black cherry, tulip tree, and pop ash. 

Hall, D. W. (n.d.). Featured creatures. University of Florida. http://entnemdept.ufl.edu/creatures/bfly/tiger_swallowtail.htm

Question of the Week

What are the nearest human-dominated habitats and how do they influence the ecosystem dynamics of your habitat?

    The nearest human-dominated habitats are the Merry Lea Sustainable Farm and Reith Village (which houses undergrad students) on one side of Thomas Woods. On the other side is the Wood Perennial Project (as mentioned in previous blogs). 

    

    The Farm could impact Thomas Woods in some positive ways, such as offering mosquitoes a ready blood meal in the form of goats, chickens, and pigs*and the creation of a field for animals to graze in creates an edge space that many birds, insects, and animals enjoy since they can forage in the field and then nest or sleep in the woods. However, the Farm is taking up land that could otherwise be naturalized areas and not all species can exist on edge spaces. The Farm also must deal with where to to put the animal waste created by the mammals and chickens, as well as the water use for the garden and watering the animals which would come from the groundwater and wetland. 

    There are also many non-native cool season grasses in the farm fields which could potentially decrease biodiversity if they out compete the native forbs that provide forage for native insects and grow under the trees. All of these things remain true for the WPP land as well, which is as big as the Farm.     

    However, these agriculturally used lands are meant to be as sustainable as possible, with the chickens, pigs, and goats allowed to roam in different areas and they are kept to small numbers so as not to have such a big impact on the land. The pigs are even kept inside the Farm Garden area, to forage some inbetween the rows of plants. 

    This is similar to the WPP where for a couple weeks out of the year, cows are kept in the pasture of trees and bushes which grow various fruits. Multiple land uses in sustainable ways help to decrease the impact of the agriculture on the land. The cows eat the cool season grasses and some of the forbs, and the native forbs bounce back much quicker than nonnatives. And cattle/goats means no tilling of the soil which would release carbon into the air. The crops can also provide forage for the native birds that nest in Thomas Woods since they will eat many berries humans grow as crops as well, or eat the bugs that would act as pests on the crops. 

    Now, the student housing at Reith Village impacts Merry Lea differently than the Farm. The dorms are built so that all the water from sinks and washers goes down into the wetland, which Thomas Woods borders. Wetlands are sinks for pollutants, and it's important not to overload them, so special soaps are used in the wash with clothes. Polluted water in the wetland could impact the plants and wildlife in Thomas Woods which depends on the wetland as a water source. Light pollution from the houses and the light poles in Reith Village could also have an impact on insect life which is attracted to such light sources and might cause them to leave the forest. 

    Overall, the human land use definitely impacts Thomas Woods and the rest of Merry Lea's land, but Merry Lea has been very proactive about doing the least harm to get the most good. 

*I performed mosquito research at Merry Lea for 2 years as an undergrad and captured the most mosquitoes at the Barn than at any other site. 

Creative Response

    Tiger Swallowtail

    Media: Watercolor