Print Report
A1127 Artemisia pedatifida Low Scrub Alliance
Type Concept Sentence: This dwarf-shrub alliance is dominated by Artemisia pedatifida and is reported from the Pryor Mountains in the northern portion of the Bighorn Basin of south-central Montana.
Common (Translated Scientific) Name: Birdfoot Sagebrush Low Scrub Alliance
Colloquial Name: Birdfoot Sagebrush Low Scrub
Hierarchy Level: Alliance
Type Concept: The vegetation of this alliance is characterized by a moderately dense dwarf-shrub layer that is dominated by Artemisia pedatifida. Atriplex gardneri may codominate in some stands. Other woody species may include scattered Artemisia tridentata, Atriplex confertifolia, Ericameria nauseosa, Eriogonum pauciflorum, Gutierrezia sarothrae, Krascheninnikovia lanata, or Suaeda moquinii. The moderately sparse herbaceous layer is often dominated by cool-season graminoids such as Pascopyrum smithii or Elymus elymoides with lesser amounts of Bouteloua gracilis, Carex filifolia, Elymus lanceolatus ssp. lanceolatus, Poa secunda, or Pseudoroegneria spicata. Forbs are generally sparse and may include scattered Allium textile, Astragalus spp., Comandra umbellata, Machaeranthera tanacetifolia, Musineon divaricatum, Phlox hoodii, Platyschkuhria integrifolia, Vicia americana, Xylorhiza glabriuscula, or the cactus Opuntia polyacantha. Annual grasses and forbs are seasonally present. This dwarf-shrub alliance is reported from the Pryor Mountains in the northern portion of the Bighorn Basin of south-central Montana and dissected uplands of the Cheyenne River Basin in northeastern Wyoming. Stands typically occur in slight depressions on alluvial fans and terraces, dissected outwash or rolling plains, lower foothills, and badlands. Sites are flat to moderately steep, often highly eroded slopes with southern or western aspects. Soils are deep, poorly drained, and typically alkaline and saline with silt-loam to clay texture. The soil surface is mostly bare ground. Substrate is derived from shale or sandstone interbedded with shale, claystone or clay.
Diagnostic Characteristics: Dwarf-shrublands found on shale breaks in dissected alluvial fans and terraces, outwash and rolling plains, and foothills in Montana and Wyoming with mixed species where Artemisia pedatifida is the most consistent dominant.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: This description is based on stands in northeastern Wyoming (Thilenius et al. 1995) and south-central Montana (Kratz 1988, DeVelice and Lesica 1993). The other Wyoming references were not available. Similar habitats in Wyoming in the Bighorn Canyon National Recreation Area were surveyed by Knight et al. (1987), but these shrublands were not described there. Some stands have very sparse vegetation cover and may be better classified in a sparsely vegetated alliance (Kratz 1988).
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: Vegetation in this alliance has a moderately dense, deciduous dwarf-shrub layer (<0.5 m). There is also a sparse to moderately dense herbaceous layer dominated by perennial graminoids with scattered perennial forbs. Annual forbs and grasses may be seasonally present.
Floristics: Stands have a moderately dense dwarf-shrub layer that is dominated by Artemisia pedatifida. Atriplex gardneri codominates in some stands. Other woody species may include scattered Artemisia tridentata, Atriplex confertifolia, Ericameria nauseosa (= Chrysothamnus nauseosus), Eriogonum pauciflorum, Gutierrezia sarothrae, Krascheninnikovia lanata, or Suaeda moquinii (= Suaeda nigra). The moderately sparse herbaceous layer is often dominated by cool-season graminoids such as Elymus elymoides or Pascopyrum smithii with lesser amounts of Bouteloua gracilis, Carex filifolia, Elymus lanceolatus ssp. lanceolatus, Poa secunda (= Poa juncifolia), or Pseudoroegneria spicata. Forbs are typically sparse and may include scattered Allium textile, Astragalus spp., Comandra umbellata, Machaeranthera tanacetifolia, Musineon divaricatum, Phlox hoodii, Platyschkuhria integrifolia, Vicia americana, Xylorhiza glabriuscula, or the cactus Opuntia polyacantha. Annual grasses and forbs are present seasonally.
Dynamics: Harsh environmental conditions limit the abundance and species diversity of plants. Because of the poor subsurface soil drainage, the upper horizons are saturated and then completely dry out between summer rainstorms. The alternating soil-moisture extremes help create these distinctive plant communities (Thilenius et al. 1995).
Environmental Description: Vegetation included in this alliance is reported from the Pryor Mountains in the northern portion of the Bighorn Basin of south-central Montana (1250-1525 m elevation), and dissected uplands of the Cheyenne River Basin in northeastern Wyoming (1830-1600 m elevation). The climate is temperate and semi-arid, with hot and dry summers. Mean annual precipitation ranges from 25-35 cm with two-thirds occurring in the spring and early summer. Stands typically occur in slight depressions on alluvial fans and terraces, dissected outwash or rolling plains, lower foothills, and badlands. Sites are generally flat to gently sloping, or moderately steep, and often highly eroded with southern or western aspects. Soils are deep, poorly drained, and typically alkaline and saline with silt-loam to clay texture. The soil surface is mostly bare ground. Substrate is derived from shale or sandstone interbedded with shale, claystone or clay.
Geographic Range: Stands in this alliance are restricted to shale breaks and badlands terrain in south-central Montana and northeastern Wyoming.
Nations: US
States/Provinces: MT, WY
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.899080
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: GNR
Greasons: No Data Available
Concept Lineage: equivalent to A.1127
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: >< Artemisia pedatifida-Atriplex nuttallii Community Type (DeVelice and Lesica 1993)
? Artemisia pedatifida/Agropyron spicatum plant community type (Kratz 1988)
? Artemisia pedatifida Vegetation Type (Thilenius et al. 1995)
? Artemisia pedatifida/Agropyron spicatum plant community type (Kratz 1988)
? Artemisia pedatifida Vegetation Type (Thilenius et al. 1995)
- DeVelice, R. L., and P. Lesica. 1993. Plant community classification for vegetation on BLM lands, Pryor Mountains, Carbon County, Montana. Unpublished report by Montana Natural Heritage Program, Helena, MT. 78 pp.
- Faber-Langendoen, D., J. Drake, M. Hall, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, M. Russo, K. Schulz, L. Sneddon, K. Snow, and J. Teague. 2013-2019b. Screening alliances for induction into the U.S. National Vegetation Classification: Part 1 - Alliance concept review. NatureServe, Arlington, VA.
- 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.
- Kratz, A. 1988. Preliminary descriptions of Great Basin-type vegetation occurring in Carbon County, Montana, U.S.A. Proceedings of the Montana Academy of Science 48:47-56.
- Thilenius, J. F., G. R. Brown, and A. L. Medina. 1995. Vegetation on semi-arid rangelands, Cheyenne River Basin, Wyoming. General Technical Report RM-GTR-263. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO. 60 pp.