Annuals; scapose or subscapose. Stems (simple or few from, or distal to, base), unbranched, (0.1–)0.3–1.2(–1.6) dm, sparsely to densely pubescent proximally, trichomes 2 (or 3)-rayed, 0.1–0.6 mm, sometimes with simple or spurred ones, to 0.9 mm, distally usually glabrous, rarely with few trichomes. Basal leaves not rosulate; petiole obscure; blade elliptic or spatulate to obovate or suborbicular, 0.5–2.3(–3) cm × 1.5–8(–13) mm, margins entire, surfaces pubescent abaxially with stalked, 2–4-rayed trichomes, 0.1–0.5 mm, adaxially with simple trichomes, 0.6–1 mm, with stalked, 2-rayed ones, to 0.7 mm. Cauline leaves usually 0, rarely 1–3; sessile; blade similar to basal. Racemes (3–)5–12(–16)-flowered, ebracteate, (subumbellate), not elongated in fruit; rachis not flexuous, usually glabrous, rarely sparsely pubescent. Fruiting pedicels horizontal to divaricate-ascending, straight, (1–)2–7(–9) mm, glabrous or glabrate. Flowers: (late-season ones cleistogamous, apetalous); sepals oblong, 1.5–2.3 mm, pubescent, (trichomes simple); petals (rarely absent), white, spatulate, 2–4.5 × 1–1.5 mm; anthers ovate, 0.4–0.5 mm. Fruits linear to linear-oblong, plane, flattened, (5–)7–16(–20) × 1.2–2.3 mm; valves glabrous or pubescent, trichomes usually simple and antrorse, 0.1–0.3 mm, rarely with fewer, spurred or 2-rayed ones; ovules 32–88 per ovary; style 0.02–0.1 mm. Seeds oblong to ovoid, 0.5–0.8 × 0.3–0.5 mm. 2n = 16, 30, 32.

Phenology: Flowering Feb–Jun(-Aug).
Habitat: Rock outcrops, dry slopes and hillsides, prairies, glades, roadsides, disturbed sites
Elevation: 0-3000 m

Distribution

• Generated Map
• Legacy Map

Alta., B.C., Man., Ont., Sask., Ala., Ariz., Ark., Calif., Colo., Ga., Idaho, Ill., Iowa, Kans., Mass., Mich., Minn., Mo., Mont., Nebr., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., S.C., S.Dak., Tenn., Tex., Utah, Wash., Wis., Wyo.

Discussion

Draba reptans is often confused with D. cuneifolia, but the two are easily separated. The rachises and pedicels of D. reptans are usually glabrous (rarely with a few isolated trichomes); those of D. cuneifolia are always densely pubescent. Interestingly, both species show parallel variations in chromosome number; it is currently unclear whether this variation is real or the result of misidentified specimens and/or erroneous counts.

Selected References

None.

Lower Taxa

None.