Shrub to 5 m, spreading by rhizomes and forming thickets. Twigs glabrous to puberulent, reddish, becoming gray, forming thorns. Leaf blades ovate to lanceolate, 5–10 cm long, acuminate, glabrous beneath. Inflorescence 2 to 5 pedicellate flowers on short branch tips before leaves appear. Flowers: hypanthium obconic, glabrous, ca. 3 mm long; sepals lanceolate, puberulent, glandular, 3–4 mm long, reflexed; petals 5–7 mm long. Drupe a plum, 2–3 cm long, yellowish to purple, glaucous (
Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
POLLINATORS The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap:
Bombus vagans,
Bombus bifarius,
Bombus huntii,
Bombus mixtus,
Bombus ternarius,
Bombus terricola,
Bombus occidentalis,
Bombus pensylvanicus,
Bombus bimaculatus,
Bombus griseocollis, and
Bombus impatiens (Macior 1968, Heinrich 1976, Thorp et al. 1983, Colla and Dumesh 2010, Williams et al. 2014).