The bluff at Monument Hill is the northern limit of the Oakville Escarpment of Miocene era bearing sandstone. This escarpment or "cuesta" marks the boundary between the Upland Post Oak Woodlands and the Fayette Prairie environments. Here, along the bluff, eastern plant and animal communities of the woodlands and prairie coexist with an isolated colony of western species.
Numerous plants and animals common to the limestone-based soils of the Hill Country, 70 miles northwest, have been transported and deposited in this locale by the Colorado River, located at the base of the 200-foot bluff. These species flourish in pockets of alkaline soils produced through erosion of the calcareous sandstone cap of the escarpment. The occurrence of such biological diversity at one location is not singularly unique, but is uncommon, and lends itself to a beautiful place in Central Texas. Oak and cedar forests and predominately little bluestem prairie environments are intermixed throughout the park, with Mr. Kreische's old roads, trails, retaining walls, and buildings adding beauty and places of shelter to the environment. The park's nature trail has a list of more common plant and animal species and is available at the park headquarters for further study.
More information on the wildlife mentioned here: