This southeastern annual can grow throughout the year, with flowering halted only during winter; 2n = 26 (FNA 3). In Ky. it is locally abundant on river bottoms of the Mississippian Embayment. But it is virtually absent upstream within the Ohio Rv. watershed except in the Bluegrass region of nc. Ky. and se Ohio. (Boufford 1990; PL), where it occurs sporadically on disturbed ground in seasonally damp eutrophic woods, especially where deer browsing is intense. The only site in that region where JC has observed the species to be locally common is in a few acres around the Brooks' spring at Bowman's Bend (GARR). The shady woods there are remarkable also for the local abundance of Collinsia verna, and for the virtual absence of Lonicera maackii.