Rubus ursinus
Rubus trivialis
California blackberry, California or Pacific or creeping blackberry, dewberry, Douglasberry, dwarf red raspberry, Pacific blackberry, Pacific dewberry, Pacific trailing blackberry, salmonberry, trailing blackberry
southern dewberry
biennial, creeping (often growing over other vegetation), sparsely to densely hairy, eglandular or sparsely to densely sessile- to stipitate-glandular, usually strongly pruinose;
prickles moderate to dense, erect to retrorse or hooked, weak to moderately stout, 4–10 mm, narrow- to 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.
deciduous or persistent, usually ternate, sometimes simple or pinnately compound;
stipules filiform to linear, 7–17 mm;
leaflets 3(–5), terminal ovate to lanceolate, 3.5–12 × 3–10 cm, base cuneate or rounded to cordate, shallowly sharp-lobed or unlobed, margins coarsely serrate to doubly serrate, apex acute to acuminate, abaxial surfaces with slender, erect prickles on larger veins, moderately to densely hairy, eglandular, rarely sparsely sessile-glandular along midvein.
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.
terminal on short shoots, usually appearing axillary, 1–5-flowered, cymiform or racemiform.
terminal on short shoots, usually appearing axillary, 1(–3)-flowered.
prickles moderate to dense, erect, densely hairy, eglandular or sparsely to densely stipitate-glandular.
prickles and, often, bristles moderate to dense, recurved, moderately to densely hairy, sparsely to moderately sessile- to short-stipitate-glandular.
usually functionally unisexual;
petals white, in staminate flowers ovate or obovate to narrowly elliptic, 7–18 mm, in pistillate ovate to elliptic, 6–11 mm;
filaments filiform;
ovaries glabrous or hairy.
bisexual;
petals white to pink, elliptic to obovate, 10–16(–25) mm;
filaments filiform;
ovaries glabrous.
black, sometimes red or purple, rarely white, not pruinose, globose to cylindric, 1–2.5 cm;
drupelets 20–50, strongly coherent, separating with torus attached.
black, globose to ovoid, 1–1.5(–2) cm;
drupelets 10–50, strongly coherent, separating with torus attached.
= 42, 56, 63, 70, 77, 84, 91.
= 14.
Rubus ursinus
Rubus trivialis
In habit, Rubus ursinus is often reminiscent of the predominantly eastern North American, non-sympatric R. flagellaris; it is also polymorphic. Rubus ursinus comprises a polyploid spectrum dominated by octoploid and dodecaploid plants. It is an allopolyploid involving phylogenetically distant ancestors with its closest relative being the Hawaiian endemic R. macraei A. Gray. See S. W. Brown (1943) for a discussion of morphological and chromosome number variation in R. ursinus. The widespread, glaucous-stemmed, trifoliate-leaved forms of R. ursinus are vegetatively nearly identical to R. caesius. Of agricultural significance, R. ursinus is a parent of some important cultivars, including loganberry and boysenberry.
There has been uncertainty whether the name Rubus menziesii Hooker and subsequent combinations [Parmena menziesii (Hooker) Greene, R. spectabilis var. menziesii (Hooker) S. Watson, and R. ursinus var. menziesii (Hooker) Focke] pertain to R. spectabilis or R. ursinus. The protologue by Hooker describes a hairy, relatively small, procumbent plant, which is congruent with R. ursinus. The type specimen at Kew also looks like R. ursinus. In the protologue Hooker also claimed the species has red petals and suggested that it may have an affinity with R. spectabilis.
Specimens examined for this study of North American collections attributed to Rubus macrophyllus Weihe & Nees (synonym R. amplificatus Lees) are R. ursinus. If R. macrophyllus was once present in the flora area it is likely absent now; some reports of R. macrophyllus could represent hybrids. There are reports of R. ursinus hybridizing with R. bifrons and R. pensilvanicus in California (T. S. Mallah 1954; L. V. Clark and M. Jasieniuk 2012; L. A. Alice, unpubl.).
(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.)
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