This diploid (2n = 14) alien is widely distributed in eastern North America and in humid western regions, especially on medium-acid soils. To the east it is concentrated in Appalalachian and mid-Atlantic regions. The first records from Ky. were colls. by T.H. Kearney and Gm during the 1890s (Anderson 1924). It gradually became widespread, but it is not often abundant.