Physaria ludoviciana

Perennials; caudex simple or branched; densely pubescent, trichomes (sessile or short-stalked), 4–7-rayed, rays usually furcate, sometimes bifurcate, (rough-tuberculate throughout). Stems few from base, erect with outer usually decumbent, 1–3.5(–5) dm. Basal leaves (erect); blade narrowly lanceolate to linear or (outer) oblanceolate, (1–)2–6(–9) cm, margins usually entire, rarely shallowly dentate, (inner involute, outer usually flat, base usually with some simple trichomes). Cauline leaves: blade narrowly oblanceolate to linear, (1–)2–4(–8) cm, margins flat or involute. Racemes compact, (elongated and loose in fruit, densely-flowered). Fruiting pedicels (usually recurved), (5–)10–20(–25) mm. Flowers: sepals oblong to broadly elliptic, 4–7(–8) mm, (lateral pair subsaccate, median pair cucullate); petals oblanceolate or obovate, (5–)6.5–9.5(–11) mm, (claw undifferentiated from blade, or blade gradually narrowed to claw). Fruits subglobose or obovoid, usually inflated, sometimes slightly compressed, (3–)4–6 mm; valves densely pubescent, trichomes spreading, usually pubescent inside, trichomes appressed, sessile; ovules (4–)8–12(–16) per ovary; style 3–4.5(–6.5) mm. Seeds slightly flattened. 2n = 10, 20, 30.

Phenology: Flowering Apr–Jul(-Aug).
Habitat: Sandy or gravelly soils, steep hillsides, prairie pastures, clay slopes, limestone outcrops, sand dunes, open plains, sandy bluffs, rocky flats, white tuff sands
Elevation: 0-1900 m

Ariz., Calif., Colo., Ill., Iowa, Kans., Minn., Mont., Nebr., Nev., N.Mex., N.Dak., Okla., S.Dak., Utah, Wis., Wyo.

Discussion

Material previously reported as Physaria ludoviciana from Canada (Alberta, Manitoba, Saskatchewan) is here included in 6a. P. arenosa subsp. arenosa. Lesquerella argentea (Pursh) MacMillan is a later homonym that has been used for P. ludoviciana.

Selected References

None.

Lower Taxa