Bothriochloa ischaemum is a species of perennial grass in the family Poaceae, found throughout much of the world. It is commonly known as yellow bluestem. Two varieties are recognized, of which Bothriochloa ischaemum var. ischaemum is native to Europe, Asia, and Africa and naturalized elsewhere, and var. songarica is native to Asia and naturalized elsewhere. Var. songarica is an invasive weed in Texas, where it is known as "King Ranch bluestem"; it (Wikipedia)