Sometimes, a species is associated with a certain type of substrate. When this is the case, identifying these species can give you insight into the soil chemistry and geologic history in an area. I applied this idea to my site of interest: Glen Echo Park. Using  Jane Forsyth’s article, Linking Geology and Botany, I identified 4 species mentioned and then identified their associated substrate. I determined that because 3/4 of these species are associated with high lime substrate, this leads me to believe this area has high lime clay-rich substrates. There are also other species on this site associated with this substrate such as white ash.

Swamp white oak (Quercus bicolor)

Lustrous, lobed leaves

Ms. Forsyth states that these are present in “high lime, clay-rich substrates developed in the thick till of the western Ohio plains…..in slightly wetter places where standing water may last for several days or weeks” (Forsyth, 1971). 

Hemlock (Tsuga canadensis)

White lines on back of needles

Hemlock

Hemlock are present in “sandstone hills of eastern Ohio where acid, locally very dry substrates are characteristic” (Forsyth, 1971).

Redbud (Cercis canadensis)

Alternate, heart-shaped leaves

According to Ms. Forsyth, these are present in “limestone and limy substrates”(Forsyth, 1971). 

Red oak (Quercus rubra)

Bristle on tip

Red Oak

These are present in “high lime, clay-rich substrates developed in the thick till of the western Ohio plains”(Forsyth, 1971). 

References:

Forsyth, J. (1971). Linking Geology and Botany a new approach. Bowling Green State University.