Montana Field Guide

Cascades Willow is a low, mat-forming shrub with prostrate stems that arise from creeping underground branches. The firm, alternate, narrowly elliptic leaves are 10-15 mm long, have short petioles, mostly inconspicuous lateral veins, and entire margins. Foliage is sparsely long-hairy when young but becomes glabrous with age. Flowers are without petals and sepals and are borne in dense spikes (aments or catkins) at the tips of lateral branches; males and females occur on separate plants. Male flowers have 2 stamens. Female aments are 1-2 cm long with dark, long-hairy scales subtending each of the 12-25 ovaries. Fruits are glabrous to long-hairy, lance-shaped capsules that are 4-5 mm long.

Flowering in July.

Salix rotundifolia and S. reticulata have elliptic leaves with more rounded tips. Salix arctica has larger female aments and leaves that are lighter beneath than above.

Moist cliffs, talus slopes, and tundra in the upper subalpine and alpine zones.

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 fervidus, Bombus frigidus, Bombus huntii, Bombus melanopygus, Bombus ternarius, Bombus terricola, Bombus sitkensis, Bombus occidentalis, Bombus pensylvanicus, Bombus bimaculatus, Bombus griseocollis, Bombus impatiens, and Bombus suckleyi (Plath 1934, Macior 1968, Heinrich 1976, Thorp et al. 1983, Colla and Dumesh 2010, Colla et al. 2011, Koch et al. 2012, Williams et al. 2014).

STATE THREAT SCORE REASON
Threat impact not assigned because threats are not known (MTNHP Threat Assessment 2021).