Physaria montana

Perennials; caudex simple or branched, (often enlarged); densely pubescent, trichomes (sessile or short-stalked), 4-7-rayed, rays furcate or bifurcate, (tuberculate throughout). Stems simple or several from base, prostrate to erect, 0.5-2(-3.5) dm. Basal leaves: blade suborbicular or obovate to elliptic, (1-)2-5(-7) cm, margins entire, sinuate, or shallowly dentate. Cauline leaves (often secund, proximal shortly petiolate, distal sessile); blade linear to obovate or rhombic, 1-2.5(-4) cm, margins entire or shallowly dentate. Racemes dense, compact, (usually elongated in fruit). Fruiting pedicels (usually sharply sigmoid, rarely nearly divaricate-spreading and straight), 5-15(-20) mm, (stout). Flowers: sepals elliptic, 5-8.5 mm, (lateral pair boat-shaped, saccate, median pair thickened apically, cucullate); petals (yellow to orange, sometimes fading purplish), narrowly spatulate or obovate, (6-)7.5-12 mm, (claw undifferentiated from blade, or gradually narrowed to claw, slightly expanded basally). Fruits (erect), ellipsoid or ovoid, not or slightly obcompressed, (apex not compressed), (6-)7-12 mm; valves densely pubescent, sometimes sparsely pubescent inside; ovules (8-)12-20(-24) per ovary; style 3-7 mm, (sometimes pubescent). Seeds flattened. 2n = 10.

Flowering Apr-Jun(-Aug). Banks, rock outcrops, stony slopes and benchlands, from plains into mountains, in sagebrush, open scrub oak, pinyon-juniper woodland, ponderosa pine, Douglas fir on granitic, often gravelly, non-calcareous soils, rarely on calcareous soils; 1000-3300 m; Ariz., Colo., Nebr., N.Mex., S.Dak., Wyo.

Physaria montana is a rather variable species that in southwestern Colorado morphologically approaches P. rectipes and in eastern Wyoming approaches P. curvipes; it is unusual in the genus for its frequent presence on igneous, non-calcareous soils.