Gardner's Saltbush - Bird's-foot Sage Dwarf-Shrubland
Global Name:
Intermountain Dwarf Saltbush - Sagebrush Scrub
Global Rank:
G4G5
State Rank:
S4
(see reason below)
External Links
State Rank Reason
These xeric habitats have likely been relatively stable in extent and condition or experienced only minor declines. Threats are relatively low compared to most other rangeland habitats.
General Description
This National Vegetation Classification Group is composed of open, dwarf-shrublands mostly of relatively pure stands of Gardner’s saltbush (Atriplex gardneri), and in south-central Montana by Bird's-foot Sage (Artemisia pedatifida). It occurs in the Bighorn Basin in the south-central part of the state across portions of the Great Plains Region. Sites occur on clay or silt soils that are saline and alkaline. Substrates are generally derived from marine shales with sites found on windswept basins, alluvial flats and plains within the Bighorn Basin. Elsewhere, Gardner’s Saltbush is found on gentle slopes, rolling topography and badlands across the plains. Other low shrubs are sometimes present at these sites. The herbaceous layer is typically sparse with perennial forbs infrequent, while perennial grasses and annual forbs may be common at some sites. These communities are similar to G300 - Shadscale - Saltbush Shrubland and G566 - Great Plains Sparsely-Vegetated Badlands but can be distinguished by the dominant species and by total vegetation cover.
This group is equivalent to the Mat Saltbush Shrubland Ecological System.
Diagnostic Characteristics
Xeromorphic Low and Dwarf-shrubs; Salt Desert Scrub; Lowlands, Alluvial flats, Plains, Badlands Topography; Alkaline, Saline Sites; Silt or Clay Soil Textures; Bighorn Basin and Great Plains Region.
Typical Dominants: Gardner’s saltbush (Atriplex gardneri), Bird’s foot Sage (Artemisia pedatifida)
Similar Systems
Range
This group occurs in Montana from the Bighorn Basin in the south-central part of the state across portions of the Great Plains Region, with concentrations in Rosebud and Carter Counties and areas bordering the Missouri River from the Breaks to Fort Peck Dam. Extensive areas occur north of the Missouri River between and south of Malta and Glasgow. Communities dominated by Bird’s foot Sage only occur within the Bighorn Basin.
In Montana, G301 occurs in Level III and IV Ecoregions: 18b (Bighorn basin), 42 (Northwestern Glaciated Plains), and 43 (Northwestern Great Plains).
In Montana, G301 occurs or potentially occurs within these Major Land Resource Areas: 32 - Northern Intermountain Desertic Basins, 52 - Brown Glaciated Plains, 53A - Northern Dark Brown Glaciated Plains, 54 - Rolling Soft Shale Plain, 58A,B,C,D - Northern Rolling High Plains, 60A - Pierre Shale Plains, and 60B - Pierre Shale Plains, Northern Part.
Density and Distribution
Based on 2025 land cover layer. Grid on map is based on USGS 7.5 minute quadrangle map boundaries.
Mapped Distribution by County
Big Horn, Blaine, Carbon, Carter, Cascade, Chouteau, Dawson, Fallon, Fergus, Gallatin, Garfield, Glacier, Golden Valley, Hill, Judith Basin, Lewis and Clark, Liberty, Mccone, Meagher, Musselshell, Park, Petroleum, Phillips, Pondera, Powder River, Prairie, Richland, Stillwater, Sweet Grass, Teton, Toole, Treasure, Valley, Wheatland, Yellowstone
Based on 2025 land cover layer.
Spatial Pattern
Large Patch
Environment
Mat Saltbush shrublands occur on clay or silt soils that are saline and alkaline. In Montana, substrates are generally derived from marine shales with sites found on windswept basins, alluvial flats and plains within the Bighorn Basin. Gardner’s Saltbush is found on gentle slopes, rolling topography and badlands across the plains. Climate is temperate and semi-arid. Summers are generally hot, and freezing temperatures are common in the winter. Mean annual precipitation ranges from about 8-13 inches. Approximately two-thirds of the annual precipitation falls in spring and early summer. Substrates are typically saline, alkaline, fine-textured soils developed from shale or alluvium. Bare soil is common, and infiltration rates are typically low at these sites.
Vegetation
This group is composed of open, dwarf-shrublands mostly of relatively pure stands of Gardner’s saltbush (Atriplex gardneri), and in south-central Montana by Bird's-foot Sagebrush (Artemisia pedatifida). Other shrubs present at these sites, especially in southern Montana include Budsage (Artemisia spinescens), winterfat (Krascheninnikovia lanata), shortspine horsebrush (Tetradymia spinosa), Shadscale saltbush (Atriplex confertifolia) or Fourwing Saltbush (Atriplex canescens) may be present. Wyoming Big Sagebrush (Artemisia tridentata ssp. wyomingensis) can occur in patches on more favorable substrates that are less saline or alkaline. The herbaceous layer is typically sparse. Perennial forbs are infrequent and scattered in the undergrowth. Common species include smooth Woody Aster (Xylorhiza glabriuscula) and Scarlet Globemallow (Sphaeralcea coccinea). Annual species of Atriplex, Povertyweed (Monolepis nuttalliana), Goosefoot (Chenopodium) and Seepweed (Suadea) are frequently present. Perennial grasses have the highest herbaceous cover. Indian Ricegrass (Oryzopsis hymenoides), Blue Grama (Bouteloua gracilis), Bottlebrush Squirrel-tail (Elymus elymoides), Thickspike Wheatgrass (Elymus lanceolatus), Western Wheatgrass (Pascopyrum smithii), Sandberg’s Bluegrass (Poa secunda), or Alkali Sacaton (Sporobolus airoides) are the most common species found at these sites. In less saline areas, there may be inclusions of grasslands dominated by Needle-and-Thread (Stipa comata), Western Wheatgrass, or Bluebunch Wheatgrass (Elymus spicatus). Cheatgrass (Bromus tectorum) or other annual bromes can become abundant, especially in disturbed sites.
In Montana, this group is represented by 5 Associations grouped into 2 Alliances within the National Vegetation Classification, which probably covers the diversity of vegetation types within the state.
National Vegetation Classification
Download the complete NVC hierarchy for Montana
TT5 B05 Desert and Semi-desert
TT5.a S61 Cool Semi-desert
TT5.a1 F121 Cool Desert and Semi-desert Shrub-Steppe
TT5.a1.Na D040 Western North American Cool Semi-Desert Scrub and Grassland
TT5.a1.Na.4 M093 Intermountain Saltbush Scrub
TT5.a1.Na.4.a G301 Intermountain Dwarf Saltbush - Sagebrush Scrub
A1110 Atriplex gardneri Low Scrub Alliance
CEGL001438 Atriplex gardneri Dwarf-shrubland
CEGL001439 Atriplex gardneri - Picrothamnus desertorum Dwarf-shrubland
CEGL001440 Atriplex gardneri / Artemisia tridentata Dwarf-shrubland
CEGL001444 Atriplex gardneri / Achnatherum hymenoides Dwarf-shrubland
A1127 Artemisia pedatifida Low Scrub Alliance
CEGL001525 Artemisia pedatifida - Atriplex gardneri Shrubland
CEGL001526 Artemisia pedatifida / Festuca idahoensis Shrubland
CEGL001527 Artemisia pedatifida / Pseudoroegneria spicata Shrubland
*Disclaimer: Some Alliances and Associations are considered provisional. Some require further documentation to verify their occurrence in the state
and some may be modified or deleted in future revisions after collection of additional data and information.
Dynamic Processes
The harsh environmental conditions of these sites slow down community dynamics. Following disturbance, the same species or species similar in stature or appearance often succeed each other. Fire frequency was historically very low in these communities. Heavy sheep grazing practices can significantly impact vigor and cover of the principal shrub species, leading to an increase of cheatgrass and other exotic annual forbs. Sites infested with cheatgrass are changing the dynamics of these communities by increasing fire potential, severity and spread.
Management
Heavy grazing pressure can result in the loss of the most common perennial grasses at these sites and lead to an abundance cheatgrass and other annual bromes and forbs.
Restoration Considerations
Gardner’s saltbush has an extensive, highly branched root system and tolerates poor site conditions. It has been used to stabilize soils and to reclaim disturbed sites (Clarke and others 1943; Carlson and others 1984). It was one of only two species to establish on coal mine spoils in Wyoming (Frischknecht and Ferguson 1984).
Species Associated with this Community
- How Lists Were Created and Suggested Uses and Limitations
Animal Species Associations
Please note that while all vertebrate species have been systematically associated with vegetation communities, only a handful of invertebrate species have been associated with vegetation communities and invertebrates lists for each vegetation community should be regarded as incomplete. Animal species associations with natural vegetation communities that they regularly breed or overwinter in or migrate through were made by:
- Using personal observations and reviewing literature that summarize the breeding, overwintering, or migratory habitat requirements of each species (Dobkin 1992, Hart et al. 1998, Hutto and Young 1999, Maxell 2000, Werner et al. 2004, Adams 2003, and Foresman 2012);
- Evaluating structural characteristics and distribution of each vegetation community relative to the species' range and habitat requirements;
- Examining the observation records for each species in the state-wide point observation database associated with each vegetation community;
- Calculating the percentage of observations associated with each vegetation community relative to the percent of Montana covered by each vegetation community to get a measure of "observations versus availability of habitat".
Species that breed in Montana were only evaluated for breeding habitat use. Species that only overwinter in Montana were only evaluated for overwintering habitat use. Species that only migrate through Montana were only evaluated for migratory habitat use. In general, species are listed as associated with a vegetation community if it contains structural characteristics known to be used by the species. However, species are not listed as associated with a vegetation community if we found no support in the literature for the species’ use of structural characteristics of the community even if point observations were associated with it. If you have any questions or comments on animal species associations with vegetation communities, please contact the Montana Natural Heritage Program's Senior Zoologist.
Plant Species Associations
Please note that while diagnostic, dominant, or codominant vascular plant species for a vegetation community have been systematically assigned to those communities and vascular plant Species of Concern were systematically evaluated for their associations with vegetation communities, the majority of Montana’s vascular plant species have not been evaluated for their associations with vegetation communities and no attempt has been made to associate non-vascular plants, fungi, or lichens with vegetation communities. Plant species associations with natural vegetation communities were made in a manner similar to that described above for animals, but with review of Lesica et al. (2022) and specimen collection data from the Consortium of Pacific Northwest Herbaria. If you have any questions or comments on plant species associations with vegetation communities, please contact the Montana Natural Heritage Program's Program Botanist.
Suggested Uses and Limitations
Species associations with vegetation communities should be used to generate potential lists of species that may occupy broader landscapes for the purposes of landscape-level planning. These potential lists of species should not be used in place of documented occurrences of species or predicted habitat suitability models (this information can be requested at: https://mtnhp.mt.gov/requests/), or systematic surveys for species and onsite evaluations of habitat by trained biologists. Users of this information should be aware that the land cover data used to generate species associations is based on satellite imagery from 2016 and was only intended to be used at broader landscape scales. Land cover mapping accuracy is particularly problematic when the vegetation communities occur as small patches or where the land cover types have been altered over the past decade. Thus, particular caution should be used when using the associations in assessments of smaller areas (e.g., evaluations of public land survey sections). Finally, although a species may be associated with a particular vegetation community within its known geographic range, portions of that vegetation community may occur outside of the species' known geographic range.
Literature Cited
- Adams, R.A. 2003. Bats of the Rocky Mountain West; natural history, ecology, and conservation. Boulder, CO: University Press of Colorado. 289 p.
- Consortium of Pacific Northwest Herbaria. https://www.pnwherbaria.org/ Last accessed May 30, 2025.
- Dobkin, D. S. 1992. Neotropical migrant land birds in the Northern Rockies and Great Plains. USDA Forest Service, Northern Region. Publication No. R1-93-34. Missoula, MT.
- Foresman, K.R. 2012. Mammals of Montana. Second edition. Mountain Press Publishing, Missoula, Montana. 429 pp.
- Hart, M.M., W.A. Williams, P.C. Thornton, K.P. McLaughlin, C.M. Tobalske, B.A. Maxell, D.P. Hendricks, C.R. Peterson, and R.L. Redmond. 1998. Montana atlas of terrestrial vertebrates. Montana Cooperative Wildlife Research Unit, University of Montana, Missoula, MT. 1302 p.
- Hutto, R.L. and J.S. Young. 1999. Habitat relationships of landbirds in the Northern Region, USDA Forest Service, Rocky Mountain Research Station RMRS-GTR-32. 72 p.
- Lesica P., M. Lavin, and P.F. Stickney. 2022. Manual of vascular plants, 2nd Edition. Brit Press. 779 p.
- Maxell, B.A. 2000. Management of Montana's amphibians: a review of factors that may present a risk to population viability and accounts on the identification, distribution, taxonomy, habitat use, natural history, and the status and conservation of individual species. Report to U.S. Forest Service Region 1. Missoula, MT: Wildlife Biology Program, University of Montana. 161 p.
- Werner, J.K., B.A. Maxell, P. Hendricks, and D. Flath. 2004. Amphibians and reptiles of Montana. Missoula, MT: Mountain Press Publishing Company. 262 p.
- Species of Concern Associated with this Community
Vascular Plants
Mammals
Birds
Reptiles
- Diagnostic, Dominant, or Codominant Plant Species for this Community
Vascular Plants
- Other Native Species Commonly Associated with this Community
Vascular Plants
Original Concept Authors
K.A. Schulz 2019
Montana Version Authors
S. Mincemoyer, T. Luna
Version Date
12/5/2024
References
- Literature Cited AboveLegend:
View Online Publication
Carlson, J. R., J. G. Schutz, and W. R. Oaks. 1983. Seed production technique of two chenopods: Gardner saltbush and winterfat. Pp. 191-195 in A. R. Tiedemann, E. D. McArthur, H. C. Stutz, R. Stevens, and K. C. Johnson, comps., Proc. Symposium on the Biology of Atriplex and related chenopods. USDA For. Serve Gen. Tech. Rep. INT-172. 309 pp.- Clarke, S. E., E. W. Tisdale, and N. A. Skogland. 1943. The effects of climate and grazing practices on short grass prairie vegetation in southern Alberta and southwest Saskatchewan. Publ. #747, Technical Bulletin #46, Dept. of Agriculture, Ottowa, Canada.
- Frischknecht, N.C. and R.B. Ferguson. 1983. Performance of Chenopodiaceae species on processed oil shale. In A. R. Tiedemann, E. D. McArthur, H. C. Stutz, R. Stevens, and K. C. Johnson, comps., Proc. Symposium on the Biology of Atriplex and related chenopods. USDA For. Serve Gen. Tech. Rep. INT-172. 309 pp.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?- Hansen, P. L., R. D. Pfister, K. Boggs, B. J. Cook, J. Joy, and D. K. Hinckley. 1995. Classification and management of Montana's riparian and wetland sites. Montana Forest and Conservation Experiment Station, School of Forestry, University of Montana, Miscellaneous Publication No. 54. 646 pp. + posters.
- Knight, D. H., G. P. Jones, Y. Akashi, and R. W. Myers. 1987. Vegetation ecology in the Bighorn Canyon National Recreation Area. Unpublished report prepared for the USDI National Park Service and University of Wyoming-National Park Service Research.
- West, N. E. 1983b. Intermountain salt desert shrublands. Pages 375-397 in: N. E. West, editor. Temperate deserts and semi-deserts. Ecosystems of the world, Volume 5. Elsevier Publishing Company, Amsterdam.
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