This weedy annual has been widely naturalized in southeastern states, especially on calcareous soils. However, it is generally rare; in the Ohio Valley virtually all records come from the Bluegrass region, Nashville Basin and scattered sites in the Ridge & Valley region (K, SE). Moreover, most Ky. colls. were made during 1934-61, and none after 1970. Its disappearance must reflect some change in farmland management, such as decline in sheep pasture and conversion of marginal pastures to fescue (Festuca arundinacea). To call this an "invasive species" (SE) may be misguided.