Geobotany is the study of the relationship with plants and their geographic environment and the substances they live on.

Ohio is broken into two different geological parts. The first part consists of a limestone sediment and makes up the Western part of Ohio. The limestone is easily susceptible to erosion and so over many and many millions of years, the landscape of western Ohio has been worked down to a completely flat landscape. Since the western side is limestone and we said there is a split, you can expect the eastern side to be different, and it is. The eastern region of Ohio has sandstone as its underlying rock. Eastern Ohio also has some shale which adds onto the topography as well. The sandstone combines and creates a natural form of cement which is resistant to erosion, while the shale is more susceptible and more easily eroded. This causes the landscape to have many valleys, but to also have steep-sided sandstone hills and capped hills.

The divide is due to the horizontal layers of the rocks. The lowest and oldest being the limestone, which is topped by shale, and finally topped with sandstone. This is exemplified in a more vertical visual in the form of an arch. Once erosion began, the process of creating the Appalachian mountains also began. With the eastern portion of Ohio being more resistant to erosion, it is safe to say the arch is lowest there. The opposite can be said about the western portion of Ohio. The arch is highest there and resulted in more erosion. This erosion is mostly due to the Teays River. (The word sounds like taze, as in, “He just got tazed, how funny.”)The Teays River flowed for 200 million years and eroded the rocks across Ohio and only stopped due to glaciers during the Ice Age. (Blame it on the squirrel. He ruins everything.)

The Pleistocene glaciers invaded Ohio a couple hundred thousand years ago, but were greatly slowed by the steep-sided sandstone hills in eastern Ohio. This caused the glacier to not move any further south than the football home of Canton. (That’s some hall of fame defense right there!) The glacier was however able to work further south in the western portions of Ohio and made it to Northern Kentucky.

A till is defined as the deposit of an unsorted mixture of sand, silt, clay, and boulders. Tills deposit sediments that reflect the original bedrock of the said area. The western Ohio glacial till was rich with lime and clay, while eastern Ohio had much less lime and clay. Eastern Ohio did have large portions of lime and clay near the sandstone hills as the ice moved from limestone to sandstone.

Plants in western Ohio have poor drainage and are not aerated well in contrast to their eastern counterparts. The pH is very limey, which is not as acidic as eastern Ohio. Western Ohio does however have an abundance of plant nutrients for their plants. The soil does not absorb much of the water and it stays on the surface level. In eastern Ohio, the pH is a lot more acidic. The water does not get absorbed much too and there is run off due to the shale being impermeable. The eastern Ohio environments are not as abundant in plant nutrients due to the acidity.

Sweet buckeye does not occur inside the glacial boundary and this is due to their troubles with repopulating in high lime tills. It is also a mystery as to why it does not appear farther north. This could be due to climate because there should be no issue geologically. Hemlock on the other hand is seen very far north past the glacial boundary. This is due to cool and moist environments in valleys with sandstone. As for rhododendron, it is south of the glacial boundary, yet it is thought to have lived in the Appalachian highlands and have migrated downward due to the Teays river drainage.

5 species of trees/shrubs that have a distribution generally limited to limestone or limey substrates (such as Ohio’s Lake Erie islands).

  • Blue Ash (Fraxinus quadrangulata)
  • Hawthorn (Crateagus mollis)
  • Sedge (Carex eburnea)
  • Hop Hornbeam (Ostrya virginiana)
  • Hackberry (Celtis occidentalis)


5 species of trees/shrubs that have a distribution generally limited to high-lime, clay-rich substrates developed in the thick glacial till of western Ohio

  • Sugar Maple (Acer saccharum)
  • Red Oak (Quercus borealis)
  • Beech (Fagus grandifolia)
  • Shagbark Hickory (Carya ovata)
  • White Oak (Quercus alba)


5 species of trees/shrubs that have a distribution generally limited to sandstone hill of eastern OH

  • Chestnut oak (Quercus montana)
  • Mountain laurel (Kalmia latifolia)
  • Sourwood (Oxydendrum arboreum)
  • Pink ladies’ slipper (Cypripedium acaule)
  • Mountain maple (Acer spicatum)


Cedar Bog (which is not really a bog)

Cedar bog is a unique and special location because it is a home to many unique habitats that would not be seen elsewhere. Cedar bog is actually a fen. A fen has a similar structure to a toilet. Rainwater builds up and then is flushed out through streams. The groundwater also is neutral and clear due to the limestone in the ground. Going back to the glacier topic, the glaciers deposited sand and gravel as well as sand and limestone. These materials allow for water flow which makes this location an amazing aquifer which means it holds lots of cool ground water. Due to the bog actually being a fen, the low point in the valley gains a lot of surface water and can provide habitats to very unique plants.

Tall Goldenrod (Solidago altissima)

Sneezeweed (Helenium autumnale)

Multiflora rose (Rosa multiflora) (thorns/spines)

Multiflora rose is an woody shrub that is an invasive plant that has thorns and produces white flowers.The leaves of the multiflora rose are toothed simple leaves arranged oppositely. The plant creates large and dense thickets that are harmful to livestock, humans, and vegetation. Some fun facts about multiflora roses are that they are native to Japan and Korea and can also grow up to 13 feet in height.

Common prickly ash (Zanthoxylum americanum) (thorns/spines)

Common prickly ash is actually not apart of the ash family. The prickly ash has  pinnately compounded leaves that can grow up to a foot long. As the name implies, the branches are prickly and possess thorns. It is said that the native Americans used the bark as a treatment for many ailments. Another fun fact is that there is a distillery in the United States that uses prickly ash in a form of bitter that is sold.


Bog goldenrod (Solidago uliginosa) (CC-9)

Canada moonseed (Menispermum canadense) (CC-5)

Alternate leafed dogwood (Cornus alternifolia) (CC-5)

Ohio goldenrod (Solidago ohioensis) (CC-9)