Part 1: Battelle Darby Metro Park
Ohio’s geology can be somewhat simplified by dividing the state into two parts: the east and the west. The eastern part of the state is made up of mostly sandstone with shale underneath it. Sandstone is difficult to erode because water dissolves the “cement” that binds its particles together very slowly. However, the shale beneath it is far more resistant to weather, leading to deep valleys of sandstone being formed throughout eastern Ohio. The western portion of the state is primarily made up of limestone, which has been more easily eroded and has led to an overall flatter landscape.
This divide was derived from Ohio’s original rock strata, which was sandstone above shale above limestone, which was shaped as a low arch before erosion began. The crest of the arch eroded to expose the oldest rocks (found in western Ohio), and the toes of the arch left younger rock layers (near the Cleveland area). The Teays River was a river that flowed in Ohio for nearly 2 million years, and is responsible for the erosion of limestone in western Ohio and sandstone and shale in eastern Ohio. The flow of the river was stopped by glaciers.
Believe it or not, a large portion of Ohio used to be covered by a glacier! The sandstone hills in eastern Ohio managed to stop glacial movement further into the state, leaving behind a glacial boundary that cuts across the state from east to west.
Glacial till is a term used to describe unorganized soil and rock parts that a glacier once picked up and subsequently left behind. This generally consists of large boulders and unsorted rock and soil pieces, including sand, silt, and clay. The glacial till found in western Ohio is highly saturated by lime and clay, whereas eastern Ohio lack lime and clay-rich till.
In western Ohio, substrate is typically described as “limey, clayey till”. The soil is impermeable, meaning that water soaks in very slowly and can cause oxygen depletion during wet periods. In contrast, eastern Ohio substrate is very permeable and allows water to pass through it easily. However, the sandstone substrate is also very acidic and provides low nutrients. The shale beneath the sandstone causes higher amounts of runoff because it is less permeable than sandstone.
The geologic makeup of Ohio is a large contributor to plant distribution across the state. Below, I will list and show photos of plants that prefer limestone or limey substrates from Battelle Darby Metro Park.
1. Hackberry (Celtis occidentalis)
Hackberry trees are monoecious, which means that they produce individual male and female flowers on the same tree. Fun!
2. Longstalk sedge (Carex pedunculata)
Sedges are considered to be somewhat of a “pioneer” species by filling in gaps that happen on forest floors.
3. Redbud (Cercis canadensis)
The redbud tree is also known as Judas tree. According to the legend, Judas hanged himself on the branch of a redbud tree, and the embarrassment of the tree caused the color of the bloom to go from white to red.
4. Chinquapin oak (Quercus muehlenbergii)
Early pioneers used the straight wood of Chinquapins to create thousands of miles of fences in the states of Ohio, Kentucky and Indiana.
5. American hop hornbeam (Ostrya virginiana)
Interestingly, American hop hornbeams have historically been considered a “weed tree” because they lack good commercial qualities and often take over understories, blocking out more “valuable” tree. I think we should all go and hug one and let it know that we appreciate it for more than what it can give us.
Honorable Mentions from Battelle Darby
While exploring Battelle Darby, I found other plants that I thought were fun and interesting! Here are the highlights of my solo-expedition:
Black haw (Viburnum prunifolium)
Fragrant sumac (Rhus aromatica)
Late purple aster (Symphyotrichum patens)
Some magnificent moss!
Some lovely lichen!
There’s a frog in there!
Some sort of horsetail plant that I couldn’t quite identify.
A fuzzy friend!
Aaaaaand I went off the trail and got burs. Whoops!