This hexaploid (2n = 60) is native to the southern Great Plains and arid southwestern regions of North America. Since 1970, it has spread through much of the lower Mississippi Valley along roads, especially interstate highways. It is much more widespread in Ky. Than indicated by the colls. Mapped here. Typical B. laguroides and B. saccharoides (Sw.) Rydb. Are more southern taxon in Central and South America (FNA 25). However, the name "saccharoides" (or "silver beardgrass") has been often misapplied to torreyana. Other alien or adventive species in this genus may be expected along roads (K, W): B. bladhii (Retz.) S.T. Blake and B. ischaemum (L.) Keng.