Darby Creek

The following pictures were taken on our class field trip to Battelle Darby Creek metro park and include some examples of limestone loving plants species, a non-native invasive plant species, and a couple pictures of some beautiful actinomorphic wildflowers.

Blue Ash

This tree is Fraxinus quadrangulata better known as blue ash. Blue ash is an example of a limestones loving plant species that prefers to grow in areas that are primarily composed of limestone, such as western Ohio. Blue ash has oppositely arranged leaves and is pinnately compound. Blue ash is native to the midwestern United States and has a history of its inner bark being used as a dye.

Chinquapin oak

This tree is Quercus muehlenbergii also known as chinquapin oak or chinkapin oak. Chinquapin oak is another example of a plant that grows well in soils derived from limestone, the kind that is found in western Ohio. The chinquapin oak is a member of the white oaks and has alternatively arranged leaves that are simple in complexity and have toothed margins.

Amur Honeysuckle

This plant is Lonicera maackii more commonly referred to as amur honeysuckle or simply honeysuckle. Amur honeysuckle is an invasive plant in Ohio. It was originally cultivated as an ornamental plant but quickly invaded new areas and pushed out other native species. Honeysuckle can be easily identified by its distinctive white flowers that turn yellow as they age.

Wild Blue Phlox

This flower is Phlox divaricata also known as blue phlox or wild blue phlox. Blue phlox is common in the eastern and parts of the midwestern United States. Blue phlox has five fused petals and five fused sepals and even though it is called blue phlox it is more light purple in appearance. Blue phlox is an example of a flower that is actinomorphic or radially symmetric.

Wood Poppy

This flower is Stylophorum diphyllum more commonly called wood poppy. Wood poppy grows most commonly in moist forests with calcareous soil. Wood poppy has four petals and its bright yellow appearance makes it stand out against the forest floor. Wood poppy is another example of an actinomorphic flower.

 

Geobotany

The following responses are referring to the article, Linking Geology and Botany… a new approach . The article and the subsequent responses discuss the relationship between Ohio’s geology and how this impacted the types of plants that occupy eastern and western Ohio.

1. If not regarded too closely the geology of Ohio can be divided into two parts. The western part of Ohio is underlain by limestone, which is nonresistant to the humid climate it is located. This has caused the rock to be eroded over millions of years and it now has a comparatively flat landscape. The eastern part of Ohio is underlain by sandstone, which is underlain by shale. Sandstone is fairly resistant to erosion as water easily passes through it, shale is not as resistant and has been eroded in places where it is not capped by sandstone. This leads to the formation of deep valleys and sandstone capped hills in eastern Ohio.

2. The reason there is a difference in the types of rocks that are present in eastern and western Ohio is that originally there were three strata of sedimentary rock, a thick limestone layers that was overlain by shale that was in turn overlain by sandstone. The rock layers were tilted into the form of a low arch before erosion began. The subsequent erosion has cut the deepest where the arch stood the tallest, exposing the oldest rocks along its crest which extends north to south through western Ohio. The oldest rocks are limestone and found throughout western Ohio and as a result of its nonresistance to erosion has created a flat plain. Away from the crest of the arch and further to the east is the youngest sandstone layer that is resistant to erosion and results in sandstone hills. Most of the erosion of the limestone in western Ohio and the shale in eastern Ohio is from a preglacial stream known as the Teays river. This river and its tributaries were present in Ohio for about 200 million years. The acivity of the river was curtailed by the advance of the glaciers of the ice age less than a million years ago.

3. When the glaciers invaded Ohio a few hundred thousand years ago their advance was greatly slowed by the presence of steep sided sandstone hills in eastern Ohio. As a result the glacial boundary is no further south than Canton Ohio. In the Western part of Ohio the limestone plains did nothing to hinder the advance of the glaciers and in this area the ice extends as far south as northern Kentucky.

Glacial Boundary

4. As the glaciers moved through Ohio they deposited materials referred to as glacial till or simply till. Till is composed of a mixture of sand, silt, clay, and boulders and it accumulated as the ice melted. Till occurs in a continuous blanket over the glaciated areas of Ohio and its material composition reflects the nature of the geologic materials over which the glacier moved. As a result the till composition differs in eastern and western Ohio. In western Ohio the glacial till is rich in lime and clay, which it picked up from the limestone bedrock it moved over. In eastern Ohio the glacial till has little lime or clay, except for at the margins of the area of sandstone hills where the ice moved from limestone bedrock onto sandstone.

5. In western Ohio the most common substrate is limey, clayey till which makes the soil high in lime but relatively impermeable to water and thus poorly drained and inadequately aerated. The supply a plant nutrients is comparatively high. In eastern Ohio the sandstone bedrock produces an acidic low nutrient substrate, which is especially dry on the tops of hills because the permeable sandstone allows water to drain easily.

6. Many plants have distributions that are primarily limited to limestone or limey substrates. A few examples include, Redbud (Cercis canadensis), red-cedar (Juniperus virginiana), fragrant sumac (Rhus aromaticia), hackberry (Celtis occidentalis), and blue ash (Fraxinus quadrangulata) which occurs at the highest abundance on the limestone substrates of the Erie Islands.

7. There are also plants that have a preference for high-lime, clay-rich substrates that was developed from the glacial till of western Ohio. A few examples of these types of plants include, sugar maple (Acer saccharum), beech (Fagus grandifolia), red oak (Quercus borealis), shagbark hickory (Carya ovata), and white oak (Quercus alba).

8. Some plants have a distribution that is primarily limited to the sandstone hills of eastern Ohio where acid and dry substrates are common. These plants include, chestnut oak (Quercus montana), sourwood (Oxydendrum arboreum), scrub pine (Pinus virginiana), pitch pine (Pinus rigida), hemlock (Tsuga canadensis).

9. Sweet buckeye does not occur anywhere inside the glacial boundary, this could be due to the difficulty of repopulation in clayey, high-lime glacial tills in the time since ice left Ohio. Sweet buckeye does not even extend as far north as the glacial bounday in eastern Ohio. Hemlock is also present in the unglaciated eastern Ohio but unlike sweet buckeye, its distribution extends far to the north of the glacial boundary. The distribution of hemlock is likely due to the plants restriction to continuously cool, moist environments such as those found in deep valleys cut into sandstone. In other words, sweet buckeye is restricted to unglaciated areas while hemlock occupies moist valley-bottom sites in sandstone. Some plants do best in mesophytic conditions, which is an environment that is not particularly wet or dry. An example of such a plant is rhododendron, whose distribution south of the glacial boundary suggests its preference for a mixed mesophytic association. Rhododendron’s distribution matches the location of valleys in the ancient Teays system and this suggests that the plant lived in the Appalachian highlands and migrated down the preglacial Teays river system.