This annual or biennial is generally uncommon to rare but locally frequent in calcareous regions of c. Ky. and c. Tenn., plus scattered sites in c. Miss., ne. Ala., nw. Ga. and perhaps n. W.Va. (Nesom 2005, FNA 20; K, W). Its original habitats may have been thin woodlands and grasslands maintained by seasonal flooding, browsing or drying. In Ky. it appears to be mostly biennial and flowers in late April to early June, but as late as August if rains persist and plants do not become overtopped. It is associated with old calcareous pastures and roadsides with late or irregular annual mowing. It is also frequent along rocky banks of the Little South Fork (PULA, WAYN). Rafinesque (1836, 2:23-24; Merrill 1949) described three taxa under Bellis from Ky., all of which can now be referred to integrifolium: (1) parviflora "on rocks, rare... very small half size of B. integrifolia"; (2) nutans, a more slender plant "in the glades of West Kentucky... flowers... same size as B. integrifolia, which grows by the millions in those glades, where I found them all in 1823"; (3) typical integrifolia, "All over the Western States... in glades." Astranthium is a remarkable, largely southwestern genus of annuals or biennials with low to high chromosome numbers. Its minute seeds have only vestigial pappus. There has been much confusion between integrifolium and the disjunct southwestern species, A. ciliatum (Raf.) Nesom; 2n = 8 in both (Neson 2005; FNA 20).