Draba pedicellata (Rollins & R.A. Price) Windham
Family: Brassicaceae
Rocky-Slope Whitlow-Grass
[Draba cusickii var. pedicellata Rollins & R.A. Price,  more...]
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Perennials; (loosely cespitose); caudex branched (with persistent leaf bases, branches sometimes terminating in sterile rosettes); scapose. Stems unbranched, (0.15-)0.3-1.3(-1.6) dm, pubescent proximally, glabrous or nearly so distally, trichomes 2- or 3-rayed and simple, 0.1-1 mm. Basal leaves rosulate; subsessile; blade oblanceolate to obovate, 0.4-1.6(-2) cm × 2-4(-6) mm, margins entire, (not ciliate), surfaces pubescent with stalked, 2-4-rayed trichomes, 0.2-0.9 mm, rarely adaxially with simple trichomes, (midvein obscure abaxially). Cauline leaves 0. Racemes 3-20(-27)-flowered, ebracteate, slightly to considerably elongated in fruit; rachis straight or flexuous, usually glabrous, rarely pubescent, trichomes simple and 2-4-rayed. Fruiting pedicels divaricate to horizontal, straight or curved upward (expanded basally or not), 4-9(-13) mm, glabrous or pubescent, trichomes simple and 2-4-rayed. Flowers: sepals broadly ovate, 1.8-2.5 mm, glabrous or pubescent, (trichomes simple and branched); petals yellow, spatulate, 3.5-5.5 × 1.5-2.2 mm; anthers ovate, 0.4-0.5 mm. Fruits lanceolate to ellipsoid or ovoid, plane (not curved), inflated or slightly flattened, (4.2-)5.3-10(-13) × 2.5-4.5(-5.5) mm; valves glabrous or pubescent, trichomes simple and short-stalked, 2-rayed, 0.05-0.3 mm; ovules 8-16 per ovary; style 0.3-1(-1.2) mm. Seeds oblong, 1.2-1.6 × 0.7-0.9 mm. 2n = 20.

Flowering May-Jul. Rock outcrops, talus, steep gravel slopes in pinyon-juniper, mixed conifer, and subalpine meadow communities; 2300-3800 m; Nev., Utah.

Draba pedicellata is known from Elko, Eureka, Nye, and White Pine counties in northeastern Nevada and to Tooele County in northwestern Utah. It was considered a variety of D. cusickii by R. C. Rollins (1993); chromosome number, morphology, and geographic distribution suggest a closer relationship to D. sphaeroides. For a detailed discussion and comparison of these species, consult M. D. Windham (2004). N. H. Holmgren (2005b) divided D. pedicellata into two varieties: var. pedicellata, which is found on limestone throughout the species range, and var. wheelerensis, which is found on non-calcareous substrates in White Pine County. Although var. wheelerensis has slightly more spreading pedicels on somewhat more flexuous rachises, it appears to be little more than a dwarf alpine form of the species.