Draba brachycarpa |
Draba californica |
|
---|---|---|
short-pod whitlowgrass, shortfruit Draba, shortpod Draba |
California Draba |
|
Habit | Annuals; not scapose. | Perennials; (short-lived); caudex simple or branched; sometimes scapose. |
Stems | usually branched, rarely unbranched, (0.3–)0.4–1.9(–2.2) dm, pubescent throughout, trichomes sessile, cruciform, 0.2–0.6(–0.8) mm (rays often equal, or those parallel to stem axis longer). |
unbranched or branched (few), (0.2–)0.4–0.9(–1.2) dm, pubescent throughout, trichomes stellate, 4–8-rayed, 0.05–0.5 mm. |
Basal leaves | not rosulate; petiolate; petiole (to 0.5 cm), not ciliate; blade oblanceolate to obovate, 0.5–2 cm × 2–8 mm, margins entire, surfaces pubescent, trichomes cruciform, 0.2–0.6(–0.8) mm. |
rosulate; shortly petiolate; petiole ciliate, margin not ciliate, (trichomes simple and 2-rayed, 0.3–1 mm); blade oblanceolate, 0.6–2 cm × 1.5–4(–6) mm, margins entire, surfaces pubescent with short-stalked, 4–8-rayed trichomes, 0.1–0.4 mm. |
Cauline leaves | (4–)6–11; sessile; blade lanceolate to oblong or linear, margins entire, surfaces pubescent as basal. |
0–3; sessile; blade ovate to oblong, margins entire, surfaces pubescent as basal. |
Racemes | (main branch) (20–)25–65(–74)-flowered, ebracteate, elongated in fruit; rachis not flexuous, pubescent as stem. |
3–13-flowered, ebracteate, elongated in fruit; rachis not flexuous, pubescent as stem. |
Flowers | (late ones cleistogamous, apetalous); sepals (green or pink), oblong, 0.7–1.2(–1.5) mm, pubescent; petals white, spatulate, 2–3 × 0.8–1.1 mm; anthers ovate, 0.15–0.25 mm. |
sepals (persistent until fruit maturity), oblong to ovate, 1.7–2.5 mm, pubescent, (trichomes short-stalked, 2–5-rayed); petals white or creamy white, spatulate to oblanceolate, 2.2–3 × 0.8–1 mm; anthers ovate, 0.2–0.35 mm. |
Fruiting pedicels | horizontal to divaricate-ascending, straight, (1–)1.5–4(–5) mm, pubescent, trichomes cruciform. |
ascending to divaricate-ascending, straight, (2–)4–9(–12) mm, pubescent, trichomes short-stalked, 4–8-rayed, (0.1–0.4 mm). |
Fruits | usually elliptic to linear-elliptic, rarely ovate-elliptic, plane, flattened, (2–)2.5–5(–6) × 0.9–1.4(–1.9) mm; valves glabrous; ovules 8–16(–20) per ovary; style 0.05–0.1 mm. |
lanceolate to oblong, plane, slightly flattened, (5–)6–9(–11) × 1.8–2.5 mm; valves usually pubescent, rarely glabrous, trichomes simple and short-stalked, 2- or 3-rayed, 0.05–0.25 mm; ovules 22–32 per ovary; style 0.1–0.3(–0.4) mm. |
Seeds | (winged), ovoid, 0.5–0.7 × 0.4–0.5 mm. |
oblong, 0.8–1 × 0.5–0.6 mm. |
2n | = 16. |
|
Draba brachycarpa |
Draba californica |
|
Phenology | Flowering Feb–May. | Flowering Jun–Aug. |
Habitat | Open woods, cedar glades, pastures and lawns, roadsides, disturbed sites | Grassy meadows, alpine areas, fellfields |
Elevation | 0-300 m (0-1000 ft) | 3200-4000 m (10500-13100 ft) |
Distribution |
AL; AR; AZ; FL; GA; IL; IN; KS; KY; LA; MO; MS; NC; OH; OK; OR; SC; TN; TX; VA
|
CA; NV |
Discussion | Draba brachycarpa is closely related to D. aprica and the two are sometimes confused. It is readily distinguished by having leaves with sessile (versus stalked) trichomes, glabrous (versus pubescent) fruits, and smaller (0.5–0.7 versus 0.9–1.1 mm) seeds. The records from Arizona and Oregon are based on old collections, Porter 802 (Devil’s Canyon, 22 Feb 1926, US) and Howell s.n. (near Cobarg, Willamette Valley, 7 Apr 1887, US); it is not known if these records represent introductions or remnants of a previously wider distribution. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Although originally treated as a variety of Draba cuneifolia, D. californica is but distantly related to that species. Instead, ongoing studies (L. Allphin and M. D. Windham, unpubl.) suggest that it may be an allopolyploid resulting from hybridization between D. albertina and D. breweri. The species is restricted to the White Mountains in Mono County, California, and adjacent Esmeralda County, Nevada. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 7, p. 296. | FNA vol. 7, p. 298. |
Parent taxa | Brassicaceae > tribe Arabideae > Draba | Brassicaceae > tribe Arabideae > Draba |
Sibling taxa | ||
Synonyms | Abdra brachycarpa | D. cuneifolia var. californica |
Name authority | Nuttall ex Torrey & A. Gray: Fl. N. Amer. 1: 108. (1838) | (Jepson) Rollins & R. A. Price: Aliso 12: 19. (1988) |
Web links |