Rubus nivalis |
Rubus trivialis |
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dwarf snow bramble, snow bramble, snow dewberry, snow dwarf bramble, snow raspberry |
southern dewberry |
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Habit | Shrubs, to 1.5 dm, armed. | Shrubs, to 3(–7) dm, sometimes climbing higher through other vegetation, moderately to densely armed. |
Stems | perennial, creeping, sparsely hairy, glabrescent, eglandular, not pruinose; prickles sparse, strongly retrorse, stout, to 1 mm, broad-based. |
biennial, initially low-arching, then falling and creeping (or climbing through other vegetation), glabrous or moderately hairy, sparsely to densely short- to long-stipitate-glandular, not pruinose; prickles moderate to dense, recurved, sometimes distally slender, 1–4 mm, broad-based; bristles absent or sparse to dense, erect to retrorse, red to purple, rarely green, slender, weak, gland-tipped. |
Leaves | evergreen, simple or ternate; stipules adnate to petioles, broadly elliptic to ovate, (6–)8–10 mm; blade ovate to cordate, (2.5–)3–5(–8) cm, lobe or leaflet base cordate, shallowly 3-lobed, margins coarsely, singly or doubly dentate, apex acute to obtuse, abaxial surfaces with prickles along midveins, glabrous or sparsely hairy, eglandular, both surfaces lustrous fresh. |
persistent or semipersistent, ternate to palmately compound, lustrous; stipules filiform, linear, or lanceolate, 2–12(–15) mm; leaflets 3–5, terminal narrowly elliptic or ovate to obovate, 2–8.5 × 0.7–4.5 cm, base rounded to cuneate, unlobed, margins moderately to coarsely serrate to doubly serrate, apex acute to acuminate, abaxial surfaces with hooked prickles on midvein, glabrous or sparsely to moderately hairy, eglandular or sparsely short-stipitate-glandular along central vein. |
Inflorescences | 1–2-flowered. |
terminal on short shoots, usually appearing axillary, 1(–3)-flowered. |
Pedicels | prickles scattered, retrorse, moderately to densely hairy, eglandular. |
prickles and, often, bristles moderate to dense, recurved, moderately to densely hairy, sparsely to moderately sessile- to short-stipitate-glandular. |
Flowers | bisexual; petals magenta to pink, elliptic to oblanceolate or spatulate, (5–)8–10 mm; filaments filiform; ovaries moderately hairy, styles glabrous. |
bisexual; petals white to pink, elliptic to obovate, 10–16(–25) mm; filaments filiform; ovaries glabrous. |
Fruits | red, hemispheric, 0.4–1 cm; drupelets 3–10, not coherent, separating from torus. |
black, globose to ovoid, 1–1.5(–2) cm; drupelets 10–50, strongly coherent, separating with torus attached. |
2n | = 14. |
= 14. |
Rubus nivalis |
Rubus trivialis |
|
Phenology | Flowering Jun–Sep. | Flowering Jan–Jun. |
Habitat | Moist, semishaded forests, glades, moist soil, logged areas | Open woodlands, savannas, prairies, meadows, sand dunes, disturbed areas, dry to seasonally wet soil |
Elevation | 0–1700 m (0–5600 ft) | 0–200 m (0–700 ft) |
Distribution |
CA; ID; OR; WA; BC
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AL; AR; FL; GA; IL; KS; KY; LA; MO; MS; NC; OK; SC; TN; TX; VA; Mexico (Coahuila, Nuevo León, Tamaulipas)
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Discussion | Rubus nivalis is recognized by its creeping, prickly stems, simple to ternate, evergreen leaves, broadly elliptic to ovate stipules, two leaflets, relatively small flowers, and magenta to pink petals. Its closest relative is likely the Mexican R. pumilus Focke. Asian species previously classified in subg. Chamaebatus (Focke) Focke are hexaploid (M. M. Thompson 1997) and not phylogenetically close; R. nivalis appears to be sister to all blackberries of subg. Rubus (L. A. Alice and C. S. Campbell 1999; Alice et al. 2008). The fruits of Rubus nivalis are eaten fresh, stewed, and canned by the Hoh and Quileute Indians (A. B. Reagan 1936). The only known specimen of Rubus nivalis from California was collected in 1961 from Del Norte County at 1250 m near the Oregon border. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Rubus trivialis is distinguished from other species of Rubus by its frequently glandular-bristly and generally creeping stems, abundant recurved prickles, and typically persistent or semipersistent, lustrous primocane leaves with relatively narrow leaflets. Although emerging primocanes typically reach to 30 cm above the ground, vigorous plants can have new primocanes standing erect to 70 cm that later fall to the ground or onto adjacent vegetation as they continue to enlarge. L. H. Bailey (1941–1945) believed that there was no clear separation between members of sect. Persistentes Fernald (referred to by Bailey as sect. Verotriviales [illegitimate sectional name for R. trivialis and associated species]) and sect. Procumbentes (by Bailey as sect. Flagellares; including R. flagellaris and related species). All characteristics that he recognized for distinguishing sect. Persistentes from sect. Procumbentes are often present in the latter, with the exception of hispid-setose stems, and glabrous plants of R. trivialis are difficult to distinguish from some plants of R. flagellaris; to include the latter species within the former would be reasonable. Rubus ×inferior L. H. Bailey is a putative hybrid of R. trivialis and R. cuneifolius. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 45. | FNA vol. 9, p. 54. |
Parent taxa | Rosaceae > subfam. Rosoideae > tribe Rubeae > Rubus | Rosaceae > subfam. Rosoideae > tribe Rubeae > Rubus |
Sibling taxa | ||
Synonyms | R. agilis, R. continentalis, R. duplaris, R. ictus, R. lucidus, R. macvaughii, R. mirus, R. nessianus, R. riograndis, R. rubrisetus, R. sons, R. tallahasseanus | |
Name authority | Douglas: in W. J. Hooker, Fl. Bor.-Amer. 1: 181. (1832) | Michaux: Fl. Bor.-Amer. 1: 296. (1803) |
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