Ozark Hill Prairie
Location
Ecological and Physical Description
The RNA contains relatively undisturbed examples of hill prairie, dry upland forest, dry-mesic upland forest, and mesic upland forest natural community types. The RNA includes the major part of the Ozark Hill Prairies Natural Area, which is significant because of its very high quality loess hill-prairie natural community and the presence of the uncommon timber rattlesnake (Crotalis horridus). The southern blazing star (Liatris squarrulosa) has been found within the RNA and will be probably be listed as a State Endangered Species in the near future.
The annual precipitation averages approximately 45 inches (114 cm), and ranges between 30 and 70 inches (76.2-177 cm). Precipitation is fairly evenly distributed throughout the year. Average annual snowfall is about 9 inches (22.8 cm), but in one-third of the winters, average annual snowfall is less than 5 inches (12.7 cm).
Climatological information is taken from the collection station at Anna, IL, which has records dating from 1951. The station is located 10.8 miles (17.4 km) to the northeast of the RNA.
The RNA is on the high bluffs that form the east wall of the Mississippi River valley in southern Illinois. It sits on a narrow, northerly-trending, main ridge with long lateral ridges in all directions. Closely-spaced and steep-sided canyons extend from floodplains to the crest. Massive gray limestone of the Devonian Bailey Formation forms the bedrock, and Devonian chert of the Grassy Knob Formation underlies the upper slopes. Thick deposits of silty loess dating from the Pleistocene are found on the ridges and to a lesser extent on the slopes. Most of the soils on the narrow ridge crests are Alford silt, with Elsah silt loam in the valleys.
Drainage from the RNA is into the Mississippi River, via Ripple Hollow on the eastern side of the ridge and via Clear Creek Ditch and Dongola and Happy Hollows on the western side of the ridge. The drainage pattern is grossly reticulate, with dendritic tributary patterns in the lateral valleys. There is a suggestion that springs may be present, associated with the Bailey limestone,
Flora and Fauna
Common Plant Species
| Scientific Name | Common Name | Category | At Risk | Notes |
|---|---|---|---|---|
| Cornus florida | Flowering dogwood | Common Shrub Species | ||
| Cercis canadensis | redbud | Common Shrub Species | ||
| Lindera benzoin | spicebush | Common Shrub Species | ||
| Asimina triloba | pawpaw | Common Shrub Species | ||
| Andropogon gerardii | Big bluestem | Common Herbaceous Species | ||
| Sorghastrum nutans | Indian grass | Common Herbaceous Species | ||
| Silphium integrifolium | prairie rosin-weed | Common Herbaceous Species | ||
| S. terebinthinaceum | basal-leaved rosin-weed | Common Herbaceous Species | ||
| Lespedeza virginica | Virginia lespedeza | Common Herbaceous Species | ||
| Toxicodendron radicans | common poison ivy | Common Herbaceous Species | ||
| Trillium flexipes | bent trillium | Common Herbaceous Species | ||
| Viola spp. | violets | Common Herbaceous Species | ||
| Asarum canadense | wild ginger | Common Herbaceous Species | ||
| Sanguinaria canadensis | bloodroot | Common Herbaceous Species | ||
| Dicentra cucullaria | Dutchman’s breeches | Common Herbaceous Species | ||
| Aquilegia canadensis | Canada columbine | Common Herbaceous Species | ||
| Polystichum acrostichoides | Christmas-fern | Common Herbaceous Species | ||
| Pteridium aquilinum | bracken fern | Common Herbaceous Species | ||
| Asplenium rhizophyllum | walking fern | Common Herbaceous Species |
Common Animal Species
| Scientific Name | Common Name | Category | At Risk | Notes |
|---|---|---|---|---|
| Odocoileus virginianus | White-tailed deer | Common Mammal Species | ||
| Canis latrans | coyote | Common Mammal Species | ||
| Urocyon cinereoargenteus | gray fox | Common Mammal Species | ||
| Procyon lotor | raccoon | Common Mammal Species | ||
| Didelphis virginiana | Virginia opossum | Common Mammal Species | ||
| Sciurus carolinensis | gray squirrel | Common Mammal Species | ||
| Lynx rufus | bobcat | Common Mammal Species | ||
| Dryocopus pileatus | Pileated woodpecker | Common Bird Species | ||
| Meleagris gallopavo | common turkey | Common Bird Species |