The answers to the questions about “Geobotany” article by Jane Forsyth.
- the geology of Ohio may be decided into two parts. The western part is underlain by limestone while eastern Ohio is underlain predominantly by sandstone. Limestone is a rock type that is relatively nonresistant in this humid climate, and this part of Ohio has been worn down to a comparatively flat landscape. Sandstone is a relatively resistant rock which is underlain by shale to the west, and erosion of the sandstone is accomplished mainly by solution of the natural cement holding the grains together by water seeping down through the rock. As the result, erosion caused the steep-sided sandstone hills or in the Cleveland region, sandstone hills.
- The original horizontal sequence of sedimentary rock strata in Ohio is a thick series of limestone layers overlain by shales which were in turn overlain by sandstones, was gently tilted into the form of a low arch before erosion began. The arch was formed by the pressure approximately 200 million years ago, and it created the original Appalachian Mountains to the east. Subsequent erosion has cut deepest where the arch stood highest, exposing the oldest rocks along its crest which extends north-south through western Ohio. These oldest rocks were limestone and found throughout western Ohio which caused the erosion down to a nearly flat plain. In eastern Ohio, the youngest rock layers is the resistant sandstone. Erosion having cut deeply into the rock strata but not having eroded it completely away, resulting in the sandstone hills. Most of this erosion of all the limestone in western Ohio and of the shale and sandstone in the east was accomplished by a famous preglacial steam Teays River. It was presented in Ohio for about 200 million years.
- The glacier was slowed by the steep-sided sandstone hills of eastern Ohio, so the glacier boundary there is no farther south and the latitude of Canton. In contrast, on the broad limestone plains of western Ohio, there was nothing to hinder the advance of the is, it extended as far south as northern Kentucky.
- The glacier till is an unsorted mixture of sand, silt, clay, and boulders. It accumulated directly by the melting of ice, and the sand and gravel materials deposited by the glacial meltwater. It occurs as a broad, continuous blanket over almost all of glaciated Ohio. In western Ohio, the glacial till is rich in lime an declaim products of the glacial abrasion of the limestone bedrock, In eastern Ohio, most of the till contains very little lime and clay, although near the margins of the area of sandstone hills where the ice moves from limestone bedrock onto sandstone, the till is higher in both lime and clay than it is elsewhere in eastern Ohio.
- On the plains of western Ohio, the most common substrate is limy, clayey till which provides a relatively impermeable soil which water does not soak in very fast and create low oxygen availability during wet period and bad drought during dry spells. The supply of plant nutrients here is comparatively abundant. In eastern Ohio, there is the very permeable sandstone bedrock, where it’s exposed, produces a very acid, low-nutrient substance which is especially dry on the tops of the hills, but it provides a supply of moisture that is continually both available and cool because it comes from springs. In addition, the shale may be presented as layers within the sandstone, and the sandstone is mantled by till which results in less acid, more moist and more nutrient-rich soils.
- Redbud, red-cedar, hack berry, blue ash, chinquapin oak. In our trip to Battle Darby Metro Park, we found many kinds of grass and sages.
- Here is the black willow (Salix fragilis) holding by Dr. Klips. It is a common willow species that is believed to be introduced here.
- This one is the big bluestem (I think it’s red-purple lol), also known as a turkey foot grass. They tend to grow in wetland or prairie or grassland ecosystems. , Its flowers are shown below.
- This is an eastern cottonwood we found at the Battle Darby Metro Park. They need to grow in bare soil and require full sun for successful germination and establishment.
- Sugar maple, beech, red oak, white oak, shagbark hickory.
- Chestnut oak, sourwood, scrub pine, hemlock, mountain maple.
- Sweet buckeye does not occur inside the glacial boundary, it may have something to do with problems of repopulation of the clayey, high-lime glacial tills in the short time. Also, climate may be one controlling factor in reason why this plant does not extend as far as the glacial boundary in eastern Ohio.
- However, hemlock is also present in unglaciated eastern Ohio, but tis distribution extends far to the north of the glacial boundary in that area. The reason for this more extensive distribution appears to be its restriction to continuously cool, moist environments. Although the till thickness re generally greater north of the glacial boundary, resulting in somewhat less acidic soils, the cool moist north-facing valleys are adequate for hemlock to be present.
- Rhododendron presents south of the glacial boundary whose distribution might suggest that they belonged to the mixed mesophytic association in Ohio, even though they do not occur everywhere throughout the unglaciated area. This species, according to Drs, E. N. Transeau and John N. Wolfe, represents one of several that lived in the Appalachian highlands and which migrated down through the preglacial Teays River system from that area north into southern Ohio. Subsequent glacial advance blocked the Teays River drainage and destroyed most of its valleys in Ohio, but the distribution of rhododendron in Ohio were determined by this avenue of migration living south of the glacial boundary and near the locations of some of the main valleys of that ancient river,
The field trip in Cedar bog (fen!)
Cedar bog is a national preserve (and the first one in Ohio!) premier natural area with a lot of unique plant and animal species. It’s called bog but it actually is a fen. fens formed when glaciers retreated. Groundwater from the Mad River Valley and the Urbana Outwash percolate through hundreds of feet of gravel left behind by the glacier in the Teays River. The result is anaerobic (oxygen-free) soils due to the slow rate at which oxygen diffuses into waterlogged soil. In addition to the water that feeds the bog, the glacier also left behind plants that are unique to Cedar Bog. Grasses and sedges are common plants in fens and fens often look like meadows and there are many plants that are rare or endangered.
For the scavenger hunt assignment, I needed to find two plants with lobed leaves. The first one I found is this sugar maple (Acer saccharum). They are limited by the Appalachians mountain in Ohio. As for how to identify them, they have oppositely arranged palmately five-lobed leaves, the basal lobes are relatively small, while the upper lobes are larger and deeply notched ( but not as deep as silver maple🍁)
The second one is the white oak (Quercus alba). They have alternately arranged pinnately leaves with 7-9 round lobes. One fact about them is that although they are long-lived, their sexual maternity begins at around 20 years, but the tree does not produce large crops of acorns until its 50th year and the amount varies from year to year.
We had seen a lot of plants in the Cedar Bog Natural Preserve. This is a ironweed (Vernonia noveboracensis). It is under Asteraceae family, it is a herbaceous plant with alternate, simple leaves. According to the FQAI, it has a CC value of 3 which means that it has a intermediate range of ecological tolerance.
The second one is this white flower called fen grass of parnassus (Parnassia glauca). It’s a flower herb under celastraceae with distinct veins on the petal. According to the FQAI, it has a 10 CC value!! This means that it has a very limited range of ecological tolerance, they only grow in fens or wetland area in the northeastern United States and southeastern Canada.
The next one is the alternate-leaved dogwood (Cornus alternifolia). It is a small deciduous shrub or tree with characteristic horizontal layers separated by gaps, with a flat-topped crown. Their leaves are alternately arranged, not like other species in Cornus. This species has a CC value of 5 which has an relatively intermediate range of ecological tolerance.
The last one is the white snake root (Ageratina altissima). It is a poison herb under family Asteraceae, native to eastern and central North America. According to the Ohio vascular database, it has a CC value of 6, not so common and need a stable or near “climax” community. As the white snake roots are consumed by cattle, the meat and milk become contaminated with the toxin. And, when milk or meat containing the toxin is consumed, the poison is passed on to humans.