Physiognomy and Structure: No Data Available

Floristics: This plant association is a tall (1.5-2.5 m [5-8 feet]), deciduous shrubland with an open canopy of willows and a thick understory of grasses and sedges. The willow canopy is dominated by Salix monticola (10-80% cover), although other species (with percent cover) may include Salix geyeriana (4-40%), Salix brachycarpa (2-28%), Salix drummondiana (1-20%), Salix ligulifolia (= Salix eriocephala var. ligulifolia) (1-11%), and Salix boothii (1%). Betula occidentalis and Dasiphora fruticosa ssp. floribunda can reach up to 10% cover. Ribes spp. are often present in low abundance. The undergrowth is dominated by patches of Carex utriculata (1-44% cover), but Carex aquatilis (1-11% cover), Deschampsia cespitosa, and Calamagrostis canadensis are often present as well. Total forb cover is generally <10% and may include Agrostis scabra, Caltha leptosepala, Cardamine cordifolia, Geum macrophyllum, Mertensia ciliata, and Heracleum maximum (Kittel et al. 1997b, Carsey et al. 2003a, 2003b).

Dynamics:  Salix monticola appears to be less tolerant of browsing pressure than other tall montane willow species. It responds to heavy browsing pressure in the same way that Salix geyeriana does; it forms the classic "mushroom" shape with over browsing by deer and cattle (Hansen et al. 1995). Carex species can be heavily grazed by livestock in narrow riparian areas in mid-elevation rangelands. Improper grazing by livestock in this plant association can dry sites, increase non-native cover, and reduce the vigor of willow root structure. The wet and often saturated soils of this plant association are also vulnerable to compaction by livestock and heavy equipment. In order to maintain productivity and vigor of the plants and prevent damage to the soils, livestock grazing should be deferred until soils dry (Hansen et al. 1995).

Changes in the physical environment, brought on by flooding or other disturbance, can initiate successional shifts in species composition. Sediment deposition on the floodplain raises the surface higher above the water table. As aggradation, or build up, of the floodplain proceeds, the site becomes drier and the dominant graminoid understory changes. Thus Carex aquatilis-dominated stands (regardless of any overstory canopy) may shift toward Calamagrostis canadensis-dominated stands.