This is a variable tuberous perennial of east-central states (2n = 8 x 8, 12 x 8, 18 x 8). In Ky. it usually occurs in submesic or subxeric woods on fertile base-rich soils. There may be rare hybrids with bulbosa (e.g. a coll. from ROWA at KY), which usually flowers 2-3 weeks later and usually occurs on much wetter soils.To the north and west of Ky., douglassii can occur on relatively damp sites, with more chance of hybridization (Y, FNA 7). In se. Ohio, the species appears to be concentrated at bases of large trees, along with Eurybia divaricata (Glick & Matlack 2021).