The Texas Blackland Prairies
are a temperate grassland ecoregion
located in Texas
that runs roughly from the Red River
in North Texas
to San Antonio
in the south.
The Texas Blackland Prairies ecoregion covers an area of 50,300 square kilometers (19,400 square miles), consisting of a main belt of 43,000 km² and two islands of tallgrass prairie grasslands
southeast of the main blackland prairie belt; both the main belt and the islands extend northeast/southwest.
The main belt consists of oaklands and savannas and runs from just south of the Red River on the Texas-Oklahoma border through the Dallas-Fort Worth region and into southwestern Texas. The Central forest-grasslands transition lies to the north and northwest, and the Edwards Plateau savanna and the Tamaulipan mezquital the southwest.
The larger of the two islands is the Fayette Prairie, encompassing 17,000 km², and the smaller is the San Antonio Prairie of 7,000 km². The two islands are separated from the main belt by the oak woodlands of the East Central Texas forests, which surround the islands on all sides but the northeast, where the Fayette Prairie meets the Piney Woods forests.
This area was shaped by frequent fire and American bison. Large fires would frequently sweep the area, clearing shrubs and stimulating forbs and grasses. Large herds of bison also grazed on the grasses.
Because of the soil and climate, this ecoregion is ideally suited to crop agriculture. This has led to most of the Blackland Prairie ecosystem
being converted to crop production, leaving less than one percent remaining (and some groups estimate less than 0.5% to less than 0.1% remaining) and making the tallgrass prairies the most-endangered large ecosystem in North America
- Ricketts, Taylor H., Eric Dinerstein, David M. Olson, Colby J. Loucks, et al. (1999). Terrestrial Ecoregions of North America: a Conservation Assessment. Island Press, Washington DC.