Mapping is provisional since this species has been generally confused with ciliaris; see notes under that name. Thise widespread weedy species may have been present in North America since early after settlement; see Gray (1864) under Panicum. D. sanguinalis sensu stricto was recorded in Ky. by Rafinesque (#196 at US) and Short (1833); later colls. were made by Kearney, Pr and Gm during the 1890s. In 1914 Gm noted it as: "one of our most troublesome grass weeds, occurring everywhere in cultivated ground, in meadows, pastures, lawns, and along roadsides." Typical sanguinalis has Eurasian origins. Most colls. need to be rechecked for ciliaris, which is widespread in tropical to warm temperate regions where sanguinalis is rare to absent. Both sanguinalis and ciliaris have largely paired spikelets; their fertile lemmas are yellow to gray to (becoming) brown (or sometimes purplish); and their lower sheaths are pilose; 2n = 28-76 in the whole sanguinalis complex (FNA 25, Y, W).