Rubus caesius

Linnaeus

Sp. Pl. 1: 493. 1753.

Common names: European dewberry
Introduced
Treatment appears in FNA Volume 9. Treatment on page 37. Mentioned on page 31, 41, 42, 56.

Shrubs, to 3 [–10] dm, armed. Stems biennial, creeping or arching then creeping, glabrous or hairy, eglandular or sparsely sessile to short-stipitate-glandular, strongly pruinose; prickles sparse to dense, erect to retrorse, slender, 1–3 mm, narrow or broad-based. Leaves deciduous, ternate; stipules linear-lanceolate to ovate, 5–15 mm; terminal leaflets ovate, 4–14 × 3–10 cm, base rounded to shallowly cordate, unlobed or shallowly lobed, margins coarsely serrate to doubly serrate, apex acute to acuminate, abaxial surfaces with prickles on midveins or unarmed, sparsely to moderately hairy, eglandular or sparsely short-stipitate-glandular along larger veins. Inflorescences terminal on short-shoot, usually appearing axillary, 1–6-flowered, solitary flowers, cymiform, or racemiform. Pedicels unarmed or prickles sparse to dense, erect to retrorse, densely hairy, sparsely to densely sessile to short or long-stipitate-glandular. Flowers bisexual; petals white, obovate to elliptic or suborbiculate, 7–13 mm; filaments filiform; ovaries glabrous. Fruits appearing bluish, black beneath bloom, pruinose, globose, 0.5–1.5 cm; drupelets 1–5 (–20), weakly coherent, separating with torus attached. 2n = 28.


Phenology: Flowering May–Oct.
Habitat: Open woodlands, meadows, roadsides, disturbed areas
Elevation: 0–400 m

Distribution

V9 43-distribution-map.jpg

Introduced; Ont., Iowa, Ky., Mich., N.Y., Ohio, Pa., Europe, w, c Asia (to w China), also in South America (Argentina)

Discussion

Within the flora area, Rubus caesius usually produces fruit with few, relatively large drupelets; in Eurasia, fruit with more drupelets are typical, and weakly pruinose fruit have been observed.

Rubus caesius is vegetatively similar to R. flagellaris and is introduced into parts of the geographic range of the latter; see M. P. Widrlechner (1998) for a comparison of these two species. Rubus caesius shows striking vegetative similarity to pruinose, trifoliate-leaved plants of R. ursinus, with which it may have a close relationship (L. A. Alice, unpubl.). In the absence of flowers or fruit, these two species could be mistaken for one another. Rubus caesius generally has broader middle primocane leaflets than R. ursinus, but that is not a consistent difference. Rubus caesius may have been introduced into the geographic range of R. ursinus; most herbarium specimens surveyed have been inadequate to make a proper determination. On specimen labels, herbarium collectors should describe at least the color of the fruit. In the last decade, R. caesius apparently has become much more aggressive around Ithaca, New York, despite occurring there since the early twentieth century (F. R. Wesley, pers. comm.).

Selected References

None.

Lower Taxa

None.

"thin" is not a number."dm" is not declared as a valid unit of measurement for this property.

... more about "Rubus caesius"
eglandular +, with prickles +  and unarmed +
stipitate-glandular +, hairy +  and glabrous +
acute;acuminate +
Lawrence A. Alice +, Douglas H. Goldman +, James A. Macklin +  and Gerry Moore +
Linnaeus +
compound +  and simple +
opposite +  and alternate +
rounded +  and shallowly cordate unlobed or shallowly lobed +
reniform +  and orbiculate +
2 cm20 mm <br />0.02 m <br /> (30 cm300 mm <br />0.3 m <br />) +
herbaceous +  and more or less coriaceous +
black +  and bluish +
not pruinose +
stipitate-glandular +, hairy +  and glabrous +
sparse to dense +
free +  and distinct +
hairy +  and glabrous +
European dewberry +
Ont. +, Iowa +, Ky. +, Mich. +, N.Y. +, Ohio +, Pa. +, Europe +, w +, c Asia (to w China) +  and also in South America (Argentina) +
not +  and aggregated +
0–400 m +
0.5 cm5 mm <br />0.005 m <br /> (8 cm80 mm <br />0.08 m <br />) +
not +  and aggregated +
without torus +  and separating +
golden yellow +  and red or black +
coherent +
hairy +  and glabrous +
globose +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
dryish +  and fleshy +
Open woodlands, meadows, roadsides, disturbed areas +
eglandular or +  and sparsely densely glandular +
0.3 cm3 mm <br />0.003 m <br /> (1 cm10 mm <br />0.01 m <br />) +
glabrous or +  and sparsely densely pubescent +
flat +  and hemispheric +
racemiform +  and cymiform +
terminal +  and axillary +
glabrous or +  and sparsely densely pubescent +
crassinucellate +
short-stipitate-glandular +
deciduous +
ovate +  and elliptic +
1.7 cm17 mm <br />0.017 m <br /> (15 cm150 mm <br />0.15 m <br />) +
revolute +  and finely coarsely crenate +
inferior +  and superior +
clustered +, biseriate +  and superposed +
collateral +  and apical +
1 +  and 2 +
stipitate-glandular +, glabrous or +  and sparsely densely hairy +
0 (?) +  and 5 (?) +
free +  and distinct +
obovate;elliptic or suborbiculate +
0.7 cm7 mm <br />0.007 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
Flowering May–Oct. +
adnate +, free +, connate +  and distinct +
sparse +  and dense +
erect +  and retrorse +
long-stipitate-glandular +  and hairy +
sparse to dense +
broad-based +
0.1 cm1 mm <br />0.001 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
not arillate +
eglandular +, armed +  and unarmed +
persistent +
free +  and distinct +
reflexed +  and spreading +
stipitate-glandular +, hairy +  and glabrous +
lanceolate +  and long-caudate +
Introduced +
free +  and distinct +
shorter to longer +
sessile +  and eglandular +
pruinose +
scrambling +  and mounding +
arching +  and creeping +
short-stipitate-glandular;hairy;glabrous +
1 +  and several +
angled +  and terete +
palmate +  and pinnate +
adnate +  and free +
linear-lanceolate;ovate +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
persistent +
distinct +
clavate +
slender +
Dalibarda +
Rubus caesius +
species +
4 cm40 mm <br />0.04 m <br /> (14 cm140 mm <br />0.14 m <br />) +
3 cm30 mm <br />0.03 m <br /> (10 cm100 mm <br />0.1 m <br />) +
inconspicuous +
convex +  and conic +
enlarged +  and small +
fibrous +  and woody +