Physaria humilis

(Rollins) O’Kane & Al-Shehbaz

Novon 12: 324. 2002.

Common names: St. Mary’s Peak or Bitterroot bladderpod
Basionym: Lesquerella humilis Rollins Contr. Gray Herb. 214: 9. 1984
Treatment appears in FNA Volume 7. Treatment on page 644. Mentioned on page 623.

Perennials; caudex simple, (thickened with persistent leaf bases); densely (silvery) pubescent, trichomes 5- or 6-rayed, rays furcate or 3-branched. Stems simple or few to several from base, prostrate, (from below a terminal rosette of leaves, unbranched), 0.2–0.5 dm. Basal leaves: blade elliptic to broadly ovate or obovate, (1–)1.5–2.5(–3) cm, margins entire, (apex obtuse). Cauline leaves: blade spatulate, 3–7 mm, (base cuneate), margins entire. Racemes not loose, (scarcely elongated in fruit, 3–5-flowered). Fruiting pedicels (straight or slightly curved). Flowers: sepals (yellow-green), narrowly elliptic to narrowly long-triangular, 3.7–5 mm; petals oblanceolate to nearly obovate, 7–8.5 mm, (abruptly tapering to narrow claw). Fruits wider than long, apex truncate to shallowly notched, compressed (angustiseptate), 3–4 mm; valves densely pubescent, trichomes ascending to erect, sparsely pubescent inside; ovules 4 per ovary; style 2–3 mm. Seeds plump, (slightly compressed).


Phenology: Flowering Jun-early Aug.
Habitat: Steep slopes, dry summits, rocky fellfields, dry ledges
Elevation: 2700-2900 m

Discussion

Of conservation concern.

Physaria humilis is found in metamorphosed rock and detritus on the peaks of the Bitterroot Mountains.

Selected References

None.

Lower Taxa

None.