Print Report

A3736 Fraxinus anomala - Rhus trilobata - Fendlera rupicola Talus & Rock Outcrop Shrubland Alliance

Type Concept Sentence: This mixed shrub alliance of the southern Rocky Mountains encompasses shrublands dominated by Brickellia californica, Fraxinus anomala, Fendlera rupicola, Jamesia americana, Prunus virginiana, and/or Rhus trilobata occupying talus, scree, rock outcrop and moderate to steep colluvial slope sites.

Common (Translated Scientific) Name: Singleleaf Ash - Skunkbush Sumac - Cliff Fendlerbush Talus & Rock Outcrop Shrubland Alliance

Colloquial Name: Singleleaf Ash - Skunkbush Sumac - Cliff Fendlerbush Talus & Rock Outcrop Shrubland

Hierarchy Level:  Alliance

Type Concept: This shrubland alliance occurs in Colorado Plateau, southern Rocky Mountains, and Great Basin. Vegetation in this mixed, short (<2 m tall) shrubland alliance is variable. The shrub canopy has sparse to moderate cover, often with irregularly distributed dense shrub patches located below cliffs, on benches, in dry channels, on toeslopes and lower slopes, and near seeps where soil moisture is more available. Stands are often characterized by a sparse to low cover (<15% total cover) mix of xeric shrubs; Brickellia californica, Fraxinus anomala, Fendlera rupicola, and Rhus trilobata are conspicuous and usually at least codominant. At higher elevations and in microsites, mesic- and cool-site shrubs such as Jamesia americana, Prunus virginiana, Ribes cereum, Rubus deliciosus, Holodiscus dumosus, Dasiphora fruticosa ssp. floribunda, and Acer glabrum are characteristic. Many other shrub species may be present. The herbaceous layer is also variable depending on site characteristics and may include many species but none provides more than a few percent cover. Biological soil crust formation is rare on active slopes. Lichens provide large amounts of foliar cover, at times from 30-60% on more stable rock. This shrubland alliance occurs in canyons, plateaus, foothill and mountain slopes or rocky colluvial slopes and rock outcrop/large cliff faces. Elevations range from 1268 to 2715 m (4160-8900 feet). Slopes are moderate to very steep and are often oriented to the cooler north or east aspects. Soils tend to be sandy and skeletal.

Diagnostic Characteristics: Temperate cold-deciduous shrublands dominated by Brickellia californica, Fraxinus anomala, Fendlera rupicola, Jamesia americana, Prunus virginiana, and/or Rhus trilobata occupying talus, scree, rock outcrop and moderate to steep colluvial slope sites.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Associations included here not only have overlapping environmental characteristics, but floristics as well with the exception of ~Jamesia americana - (Physocarpus monogynus, Holodiscus dumosus) Rock Outcrop Shrubland (CEGL002783)$$ which has a more unique suite of species and has been added here provisionally.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: Temperate cold-deciduous shrublands with sparse to moderately dense, often patchy short-shrub layer (<20 tall) with a sparse herbaceous layer of a mixture of species.

Floristics: Vegetation in this mixed, short (<20 m tall) shrubland alliance is variable. The shrub canopy has sparse to moderate cover, often with irregularly distributed dense shrub patches located below cliffs, on benches, in dry channels, on toeslopes and lower slopes, and near seeps where soil moisture is more available. Stands are often characterized by a sparse to low cover (<15% total cover) mix of xeric shrubs; Brickellia californica, Fraxinus anomala, Fendlera rupicola, and Rhus trilobata are conspicuous and usually at least codominant. At higher elevations and in microsites, mesic- and cool-site shrubs such Jamesia americana, Prunus virginiana, Ribes cereum, Rubus deliciosus, Holodiscus dumosus, Dasiphora fruticosa ssp. floribunda, and Acer glabrum are characteristic. Many other shrub species may be present, including Artemisia bigelovii, Artemisia tridentata, Atriplex confertifolia, Cercocarpus montanus, Chrysothamnus viscidiflorus, Ephedra torreyana, Ephedra viridis, Ericameria nauseosa, Gutierrezia sarothrae, Opuntia spp., and Philadelphus microphyllus. If Quercus gambelii is present, it has low cover (<5%) and does not dominate the site. The herbaceous layer is also variable depending on site characteristics and may include many species but none provides more than a few percent cover. Achnatherum hymenoides, Artemisia dracunculus, Artemisia ludoviciana, Bouteloua gracilis, Chamaesyce fendleri, Muhlenbergia montana, Pleuraphis jamesii, Stanleya pinnata, and Xylorhiza spp. are the most consistent species. Biological soil crust formation is rare on active slopes. Lichens provide large amounts of foliar cover, at times from 30-60% on more stable rock.

Dynamics:  No Data Available
Environmental Description:  This shrubland alliance occurs in canyons, foothill, plateaus and mountain slopes or rocky colluvial slopes and rock outcrop/large cliff faces in the Colorado Plateau, southern Rocky Mountains, and Great Basin. Elevations range from 1268 to 2715 m (4160-8900 feet). Slopes are moderate to very steep and are often oriented to cooler north or east aspects. The shrubs often grow within the cracks on the rocks and around the base of the rocks where accumulations of small gravel and soil occur. The high cover of rock on the ground surface acts both to concentrate runoff and as mulch to slow evaporation from the soil. Thus, relatively mesic species are able to persist on otherwise dry sites. The unvegetated surface is mostly covered by rocks, gravel, boulders, bedrock and bare soil, with little litter or dead wood evident. Soils tend to be sandy, skeletal, with a few stands on silt loams or clay loams derived from shale.
Geographic Range: This shrubland alliance is known from canyons, plateaus and mountain slopes in the Colorado Plateau, southern Rocky Mountains, and Great Basin of Utah, Colorado, New Mexico and Nevada.

Nations: US

States/Provinces:  AZ, CA, CO, NM, NV, UT


Confidence Level: Moderate

Confidence Level Comments: No Data Available
Grank: GNR

Greasons: No Data Available
Type Name Database Code Classification Code
Class 2 Shrub & Herb Vegetation Class C02 2
Subclass 2.B Temperate & Boreal Grassland & Shrubland Subclass S18 2.B
Formation 2.B.2 Temperate Grassland & Shrubland Formation F012 2.B.2
Division 2.B.2.Nf Western North American Grassland & Shrubland Division D022 2.B.2.Nf
Macrogroup 2.B.2.Nf.1 Gambel Oak - Alderleaf Mountain-mahogany - Bitterbrush species Southern Rocky Mountain Montane Shrubland Macrogroup M049 2.B.2.Nf.1
Group 2.B.2.Nf.1.a Gambel Oak - Serviceberry species - Chokecherry Southern Rocky Mountain Montane Shrubland Group G277 2.B.2.Nf.1.a
Alliance A3736 Singleleaf Ash - Skunkbush Sumac - Cliff Fendlerbush Talus & Rock Outcrop Shrubland Alliance A3736 2.B.2.Nf.1.a
Association CEGL002765 Cliff Fendlerbush Talus Shrubland CEGL002765 2.B.2.Nf.1.a
Association CEGL002783 Five-petal Cliffbush - (Mountain Ninebark, Rockspirea) Rock Outcrop Shrubland CEGL002783 2.B.2.Nf.1.a
Association CEGL003493 California Brickellbush - Skunkbush Sumac Shrubland CEGL003493 2.B.2.Nf.1.a
Association CEGL003963 Singleleaf Ash - Skunkbush Sumac Dry Talus & Slickrock Shrubland CEGL003963 2.B.2.Nf.1.a
Association CEGL005444 Chokecherry - Mixed Shrub Talus Shrubland CEGL005444 2.B.2.Nf.1.a
Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: > Fendlera rupicola Shrubland Alliance (Coles et al. 2009a)
> Jamesia americana Shrubland Alliance (Muldavin et al. 2011b)
> Prunus virginiana Shrubland Alliance (Schulz and Hall 2011)
Concept Author(s): M.E. Hall, in Faber-Langendoen et al. (2013)

Author of Description: K.A. Schulz

Acknowledgements: We have incorporated significant descriptive information previously compiled by G. Kittel and M.E. Hall.

Version Date: 12-18-14
  • Coles, J., A. Tendick, G. Manis, A. Wight, G. Wakefield, J. Von Loh, and A. Evenden. 2009a. Vegetation classification and mapping project report, Arches National Park. Natural Resource Technical Report NPS/NCPN/NRTR--2009/253. National Park Service, Fort Collins, CO. 544 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.
  • Muldavin, E., A. Kennedy, C. Jackson, P. Neville, T. Neville, K. Schulz, and M. Reid. 2011b. Vegetation classification and map: Bandelier National Monument. Natural Resource Technical Report NPS/SCPN/NRTR--2011/438. National Park Service, Fort Collins, CO.
  • Reid, M. S., and M. E. Hall. 2010. Vegetation classification of Grand Canyon National Park. Draft report submitted to National Park Service, Fort Collins, CO.
  • Schulz, K. A., and M. E. Hall. 2011. Vegetation inventory project: Great Basin National Park. Unpublished report submitted to USDI National Park Service, Mojave Desert Inventory and Monitoring Network. NatureServe, Western Regional Office, Boulder, CO. 30 pp. plus Appendices A-H.