Tarrant County Ecoregions


Tarrant Count Ecoregions

Native plants in Texas (heck, everywhere) are impacted by the climate, soils, topography, geology, and plant communities in which they occur. On a broad scale, we can see and have measured differences between characteristics in each region. These "physiographic regions" are well delineated in Texas. The four occuring in Tarrant County, moving from West to East, are the Western Cross Timbers, the Fort Worth Prairie, the Eastern Cross Timbers, and the Blackland Prairie. Each of these have significantly different bedrocks that impact acidity, nutrient availability, texture, and hydrology (ability to hold water) of the soils. As such, they are one of the main determinants for which plant species can grow where and these designations figured prominently in the development of Ecoscape. They are described more in depth in the following pages.

Botanists rely on a range of characteristics (climate, soil, topography, geology, plant community) to predict which plants can occur where. Of course, the range of most plants overlaps, though the extent varies widely. Some plants within regions are highly specific and my not occur elsewhere OR occur even within a more narrow range than the wider physiographic region.

An example of this is the endemic Dalea reverchonii or Comanche Peak Prairie Clover. This lovely little clover occurs only in areas (Parker, Wise and Hood counties) where Walnut Clay limestone formations occur. Initially discovered in 1880 on Comanche Peak (Hood County), BRIT's own Bob O'Kennon rediscovered it there in 2003. Though most of the peak consists of another type of limestone, this little plant persists only in areas with Walnut Clay limestone. Though these two limestone types occur side by side, the plant will not grow in any but Walnut Clay.

© The Botanical Research Institute of Texas. The BRIT Ecoscapes Project is made possible by a grant from the Ann L & Carol Green Rhodes Charitable Trust.