The Southern Mixed Prairie is considered the most important western range type for livestock production (Holechek, Pieper & Herbel, 2011) and once spanned a vast area of 565,000 km2 (Van Dyne and Dyer, 1973). Debate amongst various scholarly sources has made the boundaries of the Southern Mixed Prairie ambiguous. According to one model, this rangeland area spans central Nebraska down into northern Oklahoma (U.S. Forest Service, 2005). An alternate source elaborates that the Southern Mixed Prairie encompasses eastern New Mexico to eastern Texas, and southern Oklahoma to northern Mexico (Holechek, Pieper & Herbel, 2011). Sometimes coupled with the central mixed prairie, the southern mixed prairie can span Nebraska, Kansas, Oklahoma, and Texas
