On September 8, we took a lovely field trip to Batelle Darby Metro Park. At this location, we saw two types of ecosystems: wet prairie and woodland.
Ohio’s geology can be divided into two distinct regions: eastern and western Ohio. Different underlying rock types, geological history, and landscape features characterize both. In eastern Ohio, it mostly lies in the Appalachian Plateau, while the western part belongs to the Central Lowland region. The bedrock in eastern Ohio is mostly made up of shale, sandstone, and a few coal bearing rocks, while western Ohio is mostly made up of limestone and dolomite. Eastern Ohio can be characterized by hills, ridges and valleys, while western Ohio is very flat with broad, gently rolling plains.
Sedimentary rock layers often form through the gradual deposition of sediments in water bodies, which harden over time into rock. Here’s a typical sequence found in many regions, including Ohio. Top Layer: Sandstone – This layer is formed from the compaction of sand grains, typically deposited in riverbeds, deserts, or shorelines. Sandstone is often the youngest rock layer and is more resistant to erosion, leading to features like cliffs or ridges. Middle Layer: Shale – Shale is made up of fine-grained silt and clay that settle in calm, deep-water environments like lakes or slow-moving rivers. Shale often forms beneath sandstone as the environment shifts from high-energy to low-energy depositional settings. Bottom Layer: Limestone – This layer forms in warm, shallow marine environments from the accumulation of calcium carbonate from marine organisms. Limestone is often the oldest sedimentary layer in sequences like those found in Ohio.
About 200 million years ago, during the late Paleozoic to early Mesozoic periods, tectonic forces created large-scale folds in the Earth’s crust, forming arches and basins in what is now the Midwest, including Ohio. The Arch: The Cincinnati Arch is one such structure that developed as a broad, upward fold (anticline) in the Earth’s crust. It runs from northern Kentucky through western Ohio and into Indiana. Crest of the Arch: The crest of the Cincinnati Arch is located roughly where the modern-day Ohio River now flows, near the junction of Ohio, Kentucky, and Indiana. The crest would have been the highest point of the arch, while the edges or “toes” of the arch would have sloped down into adjacent basins, such as the Michigan Basin to the north and the Appalachian Basin to the east. Low-Lying Toe of the Arch: The “toe” or outer limbs of the arch would have been located in lower-lying areas to the east and west. These low-lying areas would have eventually eroded more significantly than the crest of the arch due to weathering and water flow, contributing to the shaping of Ohio’s landscape.
The Teays River was a significant preglacial river system that flowed through Ohio and much of the Midwest. Duration: The Teays River flowed for approximately 200 million years, from the late Paleozoic era until the Pleistocene Ice Age about 2 million years ago. Effect on Landscape: The Teays River shaped much of Ohio’s ancient landscape. It carved deep valleys and drained large portions of the central United States, flowing from present-day Virginia, through Ohio, and into what is now the Mississippi River basin. The river’s valleys and tributaries influenced the formation of the Ohio River, which later took its place as the dominant waterway in the region. Curtailment of River Activity: The activity of the Teays River was curtailed by the Pleistocene glaciations. Around 2 million years ago, advancing glaciers blocked the flow of the river, filling its valleys with glacial deposits. As the glaciers receded, new drainage patterns emerged, and the Teays River was essentially obliterated. The Ohio River system developed in its place, reshaping the regional hydrology.
The landscape of Ohio affected how the glaciers were carved into Ohio. Glacial till is unsorted glacial sediment.
Time to talk about the two different substrates that can be found in Ohio. In this section we will show the vast differences between western and eastern Ohio.
Western Ohio:
Primarily composed of limestone and dolomite bedrock, which weathers to produce soils rich in calcium carbonate. This leads to calcareous soils.
Western Ohio tends to have poor drainage because the soils derived from limestone are often dense and clayey. These heavier soils hold water more readily, which can lead to slow drainage in flat areas.
Due to the denser nature of the soils, aeration is often limited. Poorly drained soils tend to become compacted, which restricts the movement of air within the soil and limits root respiration for plants.
The soil in western Ohio is generally alkaline or limey, with a pH typically ranging from 7.0 to 8.0 due to the high calcium carbonate content. This favors plants that thrive in neutral to alkaline conditions, such as certain grasses, clover, and crops like corn and soybeans.
Nutrient availability is generally good in calcareous soils because the alkaline pH prevents the leaching of important nutrients like calcium, magnesium, and potassium. However, alkaline soils may limit the availability of micronutrients such as iron, manganese, and phosphorus, which can lead to deficiencies for certain plants.
Eastern Ohio:
Eastern Ohio is primarily underlain by sandstone and shale, which weather to produce soils that are more acidic and sandy. These soils are derived from sedimentary rock layers deposited in ancient seas and swamps.
Soils in eastern Ohio generally have better drainage than in the west, especially in areas where sandstone dominates. Sandy soils are more porous, allowing water to percolate through easily, although shale layers can sometimes impede drainage in specific areas.
Due to the looser, sandier nature of the soils, aeration is typically better in eastern Ohio compared to the heavier soils of the west. The looser texture allows more air to circulate around plant roots, promoting healthy respiration and growth.
The soils in eastern Ohio tend to be more acidic, with pH values often ranging from 5.0 to 6.5. The acidic nature of the soil is due to the weathering of sandstone and shale, which lack the buffering capacity of limestone. This favors plants that thrive in acidic environments, such as oaks, hemlocks, and ferns.
In acidic soils, the availability of certain nutrients like phosphorus, calcium, and magnesium can be limited. However, nutrients like iron and aluminum are more readily available in acidic conditions. Eastern Ohio soils may require lime amendments to raise the pH and improve nutrient availability for agricultural purposes.
We started our day off in the wet prairie environment first.
In this photo, Dr. Klips is showing the two different types of grasses that are dominate in the grass prairie we were exploring for the day.
Golden rod.
Common sneezeweed.
Tall boneset.
Following an enriching experience at the wet prairie, we transitioned to Cedar Ridge to explore the captivating woodland environment.
Blue ash.
Virginia creeper.
Poison ivy.
