Montana Field Guide

This shrubland group is found in the foothills and montane zone of all mountainous areas across the state. Patches sizes are generally small. These communities occur in relatively warm, dry, upland habitats and may be dominated or co-dominated by the following shrubs: Serviceberry (Amelanchier alnifolia), Ninebark (Physocarpus malvaceus), Chokecherry (Prunus virginiana), Oceanspray (Holodiscus discolor), Bitter Cherry (Prunus emarginata), Smooth Sumac (Rhus glabra), Skunkbush Sumac (Rhus trilobata), Woods' Rose (Rosa woodsii), and Common Snowberry (Symphoricarpos albus). These shrublands often occur below treeline, within the matrix of surrounding low-elevation grasslands and sagebrush shrublands. They also occur in the ponderosa pine and Douglas-fir zones, but rarely up into the subalpine zone, where they are restricted to warm, dry sites and southerly exposures. Trees if present within the community are widely scattered. These shrublands occur on all aspects. These communities also develop near talus slopes as garlands, at the heads of dry drainages, and toeslopes in the moist shrub-steppe and steppe zones. Fire, flooding and erosion all impact these shrublands, but they typically will persist on sites for long periods.

This Group incorporates the Rocky Mountain Lower Montane-Foothill Shrubland Ecological System as well as a portion of the Rocky Mountain Montane-Foothill Deciduous Shrubland Ecological System.

Shrublands; Foothills and Montane Zones; Rocky Mountain and Western Great Plains Regions; Upland Sites; Warm, Dry Settings

Typical Dominants: Serviceberry (Amelanchier alnifolia), Ninebark (Physocarpus malvaceus), Chokecherry (Prunus virginiana), Oceanspray (Holodiscus discolor), Bitter Cherry (Prunus emarginata), Smooth Sumac (Rhus glabra), Skunkbush Sumac (Rhus trilobata), Woods' Rose (Rosa woodsii), and Common Snowberry (Symphoricarpos albus)

In Montana, these communities occur throughout the mountainous portions of the state, both east and west of the Continental Divide. It extends as far east as the Little Rockies, the Little Snowies and the Wolf Mtns in Big Horn County.

In MT, G272 occurs within these Level III Ecoregions: 15 (Northern Rockies), 16 (Idaho Batholith), 17 (Middle Rockies), 41 (Canadian Rockies) and western portions of 42 (Northwestern Glaciated Plains) and 43 (Northwestern Great Plains).

In Montana, G272 occurs within these Major Land Resource Areas: 43A - Northern Rocky Mountains and 43B - Central Rocky Mountains, 44A - Northern Rocky Mountain Valleys, and 46 - Northern and Central Rocky Mountain Foothills.

Small Patch and Large Patch

These shrubland communities occur in relatively warm, dry, upland habitats in the foothills and the montane zone of all mountainous areas across the state. Rarely, they may reach into the lower subalpine zone on warm and dry, southerly aspects. At low and mid elevations they may be found on all aspects and on slopes of various steepness, though mostly on gentle to moderate slopes. Patch sizes are generally small and dictated in part by topographic breaks, slope steepness and drainage patterns.

These communities occur in relatively warm, dry, upland habitats and may be dominated or co-dominated by the following shrubs: Serviceberry (Amelanchier alnifolia), Ninebark (Physocarpus malvaceus), Chokecherry (Prunus virginiana), Oceanspray (Holodiscus discolor), Bitter Cherry (Prunus emarginata), Smooth Sumac (Rhus glabra), Skunkbush Sumac (Rhus trilobata), Woods' Rose (Rosa woodsii), and Common Snowberry (Symphoricarpos albus). Sumac communities occupy the hottest and driest sites of the shrublands within this Group.

Graminoids and forbs are common undergrowth in these shrublands. Grasses and sedges that may be abundant vary by geography and by the specific plant association but may include Purple Three-awn (Aristida purpurea), Pinegrass (Calamagrostis rubescens), Geyer's Sedge (Carex geyeri), Rough Fescue (Festuca campestris), Idaho fescue (Festuca idahoensis), Prairie Junegrass (Koeleria macrantha), Sandberg Bluegrass (Poa secunda), and Bluebunch wheatgrass (Elymus spicatus). Cheatgrass (Bromus tectorum) and Timothy (Phleum pratense) are common introduced grasses in some of these shrublands. Species of forbs in these communities vary widely by geography and by the specific plant association. Invasive forbs are also widespread in these communities and occasionally abundant, especially Spotted knapweed (Centaurea stoebe).

Adjacent or nearby riparian communities may be dominated or co-dominated by some of the same shrub species but can be distinguished in part by occurring in riparian or floodplain zones and by the presence of other riparian shrubs or riparian herbaceous species. These riparian shrub communities are part of G526 Lowland - Foothill Riparian Shrubland.

In Montana, this group is represented by 3 Alliances and 6 Associations within the National Vegetation Classification. Additional types may exist in the state.

Fires may be frequent in these low elevation, dry shrublands. Most of the common shrubs of these communities have the potential to re-sprout following all but the most severe fires. As a result, fires help to perpetuate some of these shrublands not only by the ability to resprout but also by reducing conifer encroachment. Establishment of new shrubland communities following severe fire is possible on some formerly forested sites. Once established, these communities generally persist for long periods of time.

Information on the management of these communities is lacking at this time.

Information on restoration considerations of these communities is lacking at this time.

M.S. Reid and K.A. Schulz 2015

S. Mincemoyer, T. Luna and L. Vance

12/5/2024