Rubus ulmifolius
Rubus nivalis
elm-leaf blackberry
dwarf snow bramble, snow bramble, snow dewberry, snow dwarf bramble, snow raspberry
biennial, erect, then arching, usually moderately, rarely sparsely, hairy hairs stellate, eglandular, strongly pruinose;
prickles absent or sparse to dense, erect to hooked, stout, 3–10 mm, broad-based.
perennial, creeping, sparsely hairy, glabrescent, eglandular, not pruinose;
prickles sparse, strongly retrorse, stout, to 1 mm, broad-based.
persistent or nearly so, ternate to palmately compound;
stipules filiform to linear, 4–12 mm;
leaflets 3–5, terminal ovate, elliptic, or suborbiculate to obovate, 4–10 × 2–6(–9) cm, base rounded to cuneate, unlobed, margins finely to moderately serrate, apex acute or acuminate to attenuate, abaxial surfaces with hooked prickles on larger veins, densely white short-velutinous, hairs usually minute, eglandular.
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.
terminal, 10–60-flowered, paniculiform or thyrsiform.
1–2-flowered.
unarmed or prickles moderate to dense, erect to hooked, densely short-hairy, eglandular.
prickles scattered, retrorse, moderately to densely hairy, eglandular.
bisexual;
petals usually pink, sometimes white, obovate or elliptic to suborbiculate, 5–12 mm;
filaments filiform;
ovaries apically hairy.
bisexual;
petals magenta to pink, elliptic to oblanceolate or spatulate, (5–)8–10 mm;
filaments filiform;
ovaries moderately hairy, styles glabrous.
black, globose to ovoid, 1–1.5 cm;
drupelets 10–40, strongly coherent, separating with torus attached.
red, hemispheric, 0.4–1 cm;
drupelets 3–10, not coherent, separating from torus.
= 14.
= 14.
Rubus ulmifolius
Rubus nivalis
Rubus ulmifolius can be distinguished, especially from the closely related R. bifrons and R. vestitus, by its strongly pruinose stems, finely serrate leaflets, and lack of glands throughout. Unlike R. ulmifolius, strongly pruinose native Rubus species lack relatively large and showy pink petals. Some new stems developing from tip-rooting, and early leaves on such stems (especially in shade), are not whitened abaxially and are tomentose. Such unusual stems develop typical leaves and surfaces in parts formed later.
There has been nomenclatural confusion over unarmed plants of Rubus ulmifolius (see E. Monasterio-Huelin and H. E. Weber 1996). Rubus inermis Willdenow is an illegitimate later homonym of R. inermis Pourret, and the type specimens for both names are of poor-quality. If an unarmed variety of R. ulmifolius is to be recognized, such as occurs in California, the name var. anoplothyrsus Sudre should be used instead of var. inermis (Willdenow) Focke.
Rubus ulmifolius is attractive and is potentially weedy but relatively uncommon, found primarily in coastal California from the San Francisco Bay region southward. It probably no longer persists in New Jersey, last collected there in 1897, and it is rare in Nevada and Oregon. Rubus ulmifolius likely hybridizes with R. bifrons where they co-occur; it is one of relatively few diploid and sexually reproducing species of European blackberries.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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.)
- Local floras:
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
PNW Herbaria 
WildflowerSearch
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- Local floras:
BC, CA, OR, WA - Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria
- WildflowerSearch
- iNaturalist (observations)
- USDA Plants Database
- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
- Wikipedia
- Google Image Search
