Black twinberry is a deciduous species of shrub that is found across North America. In British Columbia, it is commonly found in the lower two thirds of the province. Habitat includes moist forests and thickets with moist nitrogen-rich soils (Douglas et al. 1998, Klinka et al. 1989). It is tolerant of fluctuating groundwater levels (Klinka et al. `989). It is readily identified by the yellow tubular flowers that occur in pairs, and the black shiny berries.
Deciduous, erect to straggly shrub, 0.5-5 m tall; young twigs 4-angled, greenish, glabrous; older stems with yellowish-grey, shredding bark.
Opposite, short-stalked, elliptic to oblanceolate or broadly lanceolate, 3-16 cm long, 2-8 cm wide, entire, rounded or tapered at base, abruptly sharp-pointed at tip, pale and glabrous or somewhat hairy beneath.
Inflorescence of short-stalked pairs of flowers cupped by large (2 - 4 cm across) involucres of 2 pairs of fused bracts, on 1-4 cm long stalks in leaf axils; corollas tubular bell-shaped, yellow, 1-2 cm long, glandular hairy on outside, scarcely 2-lipped with 5 roughly equal lobes above; corolla tubes with short thick spurs at bases.
Berries, shiny black, 0.8-1.2 cm across, paired, loosely surrounded while young by paired bracts, which darken and redden (to purplish-maroon) as they recurve from the maturing fruits.
If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.
Illustration Source: The Illustrated Flora of British Columbia
Present over the Summer
Source: The USDA
||Value / Class
Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
of field plots
species was recorded in:
BEC Zone Class
All BEC Zones (# of stations/zone) species was recorded in
|AT(6), BG(9), BWBS(388), CDF(32), CWH(256), ESSF(1667), ICH(1260), IDF(405), IMA(1), MH(1), MS(951), PP(9), SBPS(252), SBS(2975), SWB(1)|
Source: Klinkenberg 2013