Go back

Prairies

Prairies as recognized here are areas dominated by medium- to tall-statured grasses and herbaceous plants that develop on flat plains or gently undulating landscapes. They typically have deep, fertile soils and historically were almost treeless. Prairies of Tennessee likely were maintained historically by a combination of fire and grazing by megafauna. Some prairie systems however were also partly maintained by the presence of a clay fragipan which restricts the growth of tree roots and oscillates from a winter and spring wet phase to a very dry phase in summer and fall. These are referred to here as Xerohydric Hardpan Prairies. At least one prairie type in Tennessee was probably also maintained in part by the presence of dense clays which were subject to shrink-swell processes, thus restricting tree growth and favoring grasses and herbaceous plants. Prairies were most common in parts of West and Middle Tennessee but prairie-like areas also probably were also found on relativel large plain-like surfaces of the Cumberland Plateau and in wide valleys of the southern Ridge and Valley. The following prairie types are recognized here for Tennessee:

MISSISSIPPI VALLEY LOESS PLAINS

LOESS PLAIN ECOREGION

SOUTHEASTERN PLAINS

BLACK BELT ECOREGION

INTERIOR PLATEAUS

WESTERN HIGHLAND RIM ECOREGION

PENNYROYAL PLAIN ECOREGION

EASTERN HIGHLAND RIM ECOREGION

SOUTHWESTERN APPALACHIANS

CUMBERLAND PLATEAU ECOREGION


RIDGE AND VALLEY

SOUTHERN CALCAREOUS VALLEYS ECOREGION