This winter-annual is widely scattered in east-central states, centered on the central Mississippi Rv. and upper Ohio Rv. watersheds. However, it is largely restricted to damp woods on highly fertile soils, often with much patchiness and local genetic differentiation (Greenlee & Rai 1986). Although verna appears to be uniformly diploid (2n = 14), its genome size (C-value) varies greatly, from ca. 7 pg in western Ky. to 28 pg in northern Ind. (Greenlee et al. 1984). In Ky. the species is most frequent within the Bluegrass region, but even here the distribution is fragmented to a degree not explained by current habitat. In the central Bluegrass, Short )1828-9) noted: "This beautiful little plant, which is seen in profuse abundance on many parts of the Dry-ridge road to Cincinnati, is occasionally, though rarely, found in this immediate vicinity." C. verna may be most abundant where woods are recovering from past grazing, sometimes expanding within a few decades to cover 10s of acres (e.g. at Raven Run in FAYE; Campbell et al. 1995). It is generally absent in deeper woods with less obvious history of disturbance. Also, although this species is capable of some self-pollination (Kalisz et al. 2004), initial horticultural experience in Ky. suggests that small starter populations of ca. 10-100 plants may not be able to attract sufficient pollinators for persistence. However, S. Lockwood (pers. comm.) has been able to establish a population in Cincinnati, Ohio, with 1000s of plants 10-15 years after an initial introduction of no more than 100 seeds. An introduction with 100s of seeds in HART has succeeded for severak years (A. Meijer, pers. comm,).