Eustoma exaltatum subsp. russellianum
Synth. N. Amer. Fl., nomencl. innov. 11. 1999.
Corollas (3.5–)4–7 cm, lobes narrowly obovate to widely spatulate-obovate. 2n = 18 (cultivated in China), 72.
Phenology: Flowering spring–fall.
Habitat: Prairies, meadows, other open, usually moist to wet sites.
Elevation: 10–2000 m.
Distribution
Colo., Kans., Mont., Nebr., N.Mex., Okla., S.Dak., Tex., Wyo.
Discussion
The Montana record may represent an escape from cultivation, of short duration. A report of this taxon from Louisiana was based on a specimen collected in 1806, only three years after the Louisiana Purchase, and “Louisiana” probably did not refer to the present state of Louisiana.
Cultivars of subsp. russellianum have been selected for plant size and habit, corolla size and shape (usually 6–11 cm in diameter in cultivated plants), diversity in corolla color and markings, supernumerary petals, and other horticulturally significant traits. Tetraploidy has been induced through colchicine treatment. Plants with supernumerary petals often show other floral irregularities, such as tricarpellate pistils.
Selected References
None.