Print Report
A3800 Salix exigua - Salix irrorata Shrubland Alliance
Type Concept Sentence: This riparian shrubland alliance is dominated by Salix exigua, Salix irrorata, and/or Salix melanopsis. The canopy is tall (2-5 m), and typically many-branched with continuous cover of 60-100%. Communities occur along streams throughout the western U.S. They are found in streamsides, marshes and wet ditches.
Common (Translated Scientific) Name: Narrowleaf Willow - Dewystem Willow Shrubland Alliance
Colloquial Name: Narrowleaf Willow - Dewystem Willow Shrubland
Hierarchy Level: Alliance
Type Concept: Dominant species are Salix exigua, Salix interior, Salix irrorata, and/or Salix melanopsis. It is typically a monotypic stand with some herbaceous understory; however, other shrubs and trees can be present. The herbaceous stratum can have sparse to moderate cover, including a variety of pioneer species. Other codominants may include Populus fremontii, Populus deltoides, Populus angustifolia, and Acer negundo. Other shrubs within this alliance consist of Alnus incana, Cornus sericea, Rosa spp., Rubus idaeus ssp. strigosus, Ribes aureum, Ribes inerme, and other Salix species. Common herbaceous species include Artemisia ludoviciana, Epilobium spp., Equisetum spp., Fragaria virginiana ssp. glauca, Geranium spp., Hackelia spp., Maianthemum stellatum, Mertensia ciliata, Osmorhiza occidentalis, Thalictrum fendleri, and Urtica dioica. Non-native species can be abundant, such as Poa pratensis, Bromus inermis, Taraxacum officinale, and Cirsium arvense. Elevation ranges from 0 to 2950 m (0-9680 feet). These shrublands are found on open sand and gravel bars without tree canopy shading, on a wide variety of streams and rivers and even ditches. Salix exigua is one of the most common willows found throughout the western U.S. Salix irrorata has similar habitat, but a much more limited range of distribution. Stands are associated with annual flooding and inundation and will grow well into the active stream channel, where it is flooded, even in drier years. Even though flooding is frequent, surface water may not be present for much of the growing season, and the water table is well below the surface, especially in the warmer and hotter parts of the western U.S. Some stands form large, wide stands on mid-channel islands on larger rivers, or narrow stringer bands on small, rocky tributaries. Streams range widely from moderately sinuous and moderate-gradient reaches to broad, meandering rivers with wide floodplains or broad, braided channels. Many stands also occur within highly entrenched or eroding gullies.
Diagnostic Characteristics: Greater than 5% relative cover of Salix exigua, Salix interior, Salix irrorata, and/or Salix melanopsis.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: Salix interior Rowlee has been recently raised to species level and was formerly Salix exigua Nutt. subsp. interior (Rowlee) Cronquist. Stands west of the 100th meridian are included in the concept of this alliance, including those stands in eastern Wyoming, Montana, Colorado and New Mexico.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: The canopy is dominated by a tall (2-5 m), broad-leaved deciduous shrub that is typically many-branched with continuous cover of 60-100%. The herbaceous stratum is sparse to moderate cover, including a variety of pioneer species.
Floristics: Plant associations within this alliance are characterized as temporarily flooded cold-deciduous shrublands dominated by Salix exigua, Salix irrorata, Salix melanopsis, and/or Salix interior. The tall-shrub layer has 15-90% cover, ranging in height between 2-5 m. Other shrubs can occur in the canopy, including Salix eriocephala, Salix lasiolepis, Salix ligulifolia, Salix lutea, and/or Salix monticola, as well as Alnus incana, Cornus sericea, Rosa spp., Rubus idaeus ssp. strigosus (= Rubus strigosus), Ribes aureum, and Ribes inerme. Occasionally, taller Acer negundo, Alnus rhombifolia, Juglans hindsii, Populus angustifolia, Populus deltoides, Populus balsamifera, Populus fremontii, Salix gooddingii, Salix laevigata, Salix lucida, Salix amygdaloides, or Tamarix spp. occur within the tree subcanopy. The herbaceous layer varies greatly over the broad range of the alliance. It may have as much as 20-35% cover of various graminoid species, including Carex nebrascensis, Carex pellita (= Carex lanuginosa), Equisetum arvense, Muhlenbergia rigens, Panicum bulbosum, Phalaris arundinacea, and Spartina pectinata. Other common herbaceous species include Artemisia ludoviciana, Epilobium spp., Equisetum spp., Fragaria virginiana ssp. glauca (= Fragaria ovalis), Geranium spp., Hackelia spp., Maianthemum stellatum, Mertensia ciliata, Osmorhiza occidentalis, Glycyrrhiza lepidota, Thalictrum fendleri, and Urtica dioica. Non-native species can be abundant, such as Medicago sativa, Agrostis gigantea, Agrostis stolonifera, Poa pratensis, Bromus inermis, Melilotus officinalis, Taraxacum officinale, Cirsium arvense, and/or Trifolium repens. The understory can also have no herbaceous growth at all and be completely barren ground, gravels or other alluvium.
Dynamics: This alliance represents an early-seral primary successional stage on newly deposited sediments that may persist under a regime of repeated fluvial disturbance. Salix exigua, Salix interior, and Salix irrorata are highly adapted to most forms of disturbance, are prolific sprouters, and will re-establish themselves on sites dominated by other disturbance-associated species, e.g., Glycyrrhiza lepidota and Pascopyrum smithii.
Environmental Description: Plant associations within this alliance are located on floodplains and gravel bars at an elevational range between 0 and 2950 m (0-9680 feet) in the western U.S. These shrublands are found on open sandbars without canopy shading on large or small streams and rivers with sandy or cobble substrates. They are associated with annual flooding and inundation and will grow well into the active river channel, where it is flooded even in drier years. Even though flooding is frequent, surface water is not present for much of the growing season, and the water table is well below the surface, especially in warmer and drier parts of the western U.S. Some stands form large, wide stands on mid-channel islands on larger rivers, or narrow stringer bands on small, rocky tributaries. Stream reaches range widely from moderately sinuous and moderate-gradient reaches to broad, meandering rivers with wide floodplains or broad, braided channels. Many stands also occur within highly entrenched or eroding gullies. It can be found along wet ditches as well.
Soils of this alliance are typically coarse alluvial deposits of sand, silt and cobbles that are highly stratified with depth from flooding scour and deposition. The stratified profiles consist of alternating layers of clay loam and organic material with coarser sand or thin layers of sandy loam over very coarse alluvium. Occasionally, stands may occur on deep pockets of sand. The pH of the substrate ranges from 6.0-6.8 (Johnston 1987).
Soils of this alliance are typically coarse alluvial deposits of sand, silt and cobbles that are highly stratified with depth from flooding scour and deposition. The stratified profiles consist of alternating layers of clay loam and organic material with coarser sand or thin layers of sandy loam over very coarse alluvium. Occasionally, stands may occur on deep pockets of sand. The pH of the substrate ranges from 6.0-6.8 (Johnston 1987).
Geographic Range: This alliance is found throughout the lower elevations of the Interior West from Arizona to Alberta west to California and Washington.
Nations: CA,US
States/Provinces: AB, AZ, CA, CO, ID, MT, NM, NV, OR, UT, WA, WY
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.899852
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: GNR
Greasons: No Data Available
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: ? Salix spp. Series (Johnston 1987)
? Plains and Great Basin Riparian Wetlands (Brown 1982a)
? Plains and Great Basin Riparian Wetlands (Brown 1982a)
- Borchert, M., A. Lopez, C. Bauer, and T. Knowd. 2004. Field guide to coastal sage scrub and chaparral series of Los Padres National Forest. Report R5-TP-019. USDA Forest Service, Pacific Southwest Region, San Francisco, CA.
- Brown, D. E., C. H. Lowe, and C. P. Pase. 1979. A digitized classification system for the biotic communities of North America with community (series) and association examples for the Southwest. Journal of the Arizona-Nevada Academy of Science 14:1-16.
- Brown, D. E., editor. 1982a. Biotic communities of the American Southwest-United States and Mexico. Desert Plants Special Issue 4(1-4):1-342.
- Christy, S. 1973. An analysis of the woody vegetation on the South Platte River flood plain in northeastern Colorado. Unpublished thesis, University of Northern Colorado, Greeley. 82 pp.
- Cooper, D. J., and T. R. Cottrell. 1990. Classification of riparian vegetation in the northern Colorado Front Range. Unpublished report prepared for The Nature Conservancy, Colorado Field Office, Boulder. 115 pp.
- Dale, E. E., and P. M. Kuroda. 1979. Vegetation map and natural areas survey. Pages 77-82 of unspecified report [incomplete citation]. Includes USDI National Park Service memo and tables.
- Dick-Peddie, W. A. 1993. New Mexico vegetation: Past, present, and future. University of New Mexico Press, Albuquerque. 244 pp.
- Dick-Peddie, W. A., J. K. Meents, and R. Spellenberg. 1984. Vegetation resource analysis for the Velarde Community Ditch Project, Rio Arriba and Santa Fe counties, New Mexico. Unpublished final report prepared for the USDI Bureau of Reclamation, Southwestern Region, Amarillo, TX. 251 pp.
- Dorn, R. D. 1997. Rocky Mountain region willow identification field guide. Renewable Resources R2-RR-97-01. USDA Forest Service, Rocky Mountain Region, Denver, CO. 107 pp.
- Evenden, A. G. 1990. Ecology and distribution of riparian vegetation in the Trout Creek Mountains of southeastern Oregon. Ph.D. dissertation, Oregon State University, Corvallis. 156 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.
- Faber-Langendoen, D., and Midwest State Natural Heritage Program Ecologists. 1996. Terrestrial vegetation of the midwest United States. International classification of ecological communities: Terrestrial vegetation of the United States. The Nature Conservancy, Arlington, VA.
- 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. Miscellaneous Publication No. 54. Montana Forest and Conservation Experiment Station, School of Forestry, University of Montana. 646 pp. plus posters.
- Hansen, P., K. Boggs, and R. Pfister. 1991. Classification and management of riparian and wetland sites in Montana. Unpublished draft version prepared for Montana Riparian Association, Montana Forest and Conservation Experiment Station, School of Forestry, University of Montana, Missoula. 478 pp.
- Hansen, P., R. Pfister, J. Joy, D. Svoboda, K. Boggs, L. Myers, S. Chadde, and J. Pierce. 1989. Classification and management of riparian sites in southwestern Montana. Unpublished draft prepared for the Montana Riparian Association, School of Forestry, University of Montana, Missoula. 292 pp.
- Johnston, B. C. 1987. Plant associations of Region Two: Potential plant communities of Wyoming, South Dakota, Nebraska, Colorado, and Kansas. R2-ECOL-87-2. USDA Forest Service, Rocky Mountain Region. Lakewood, CO. 429 pp.
- Jones, G. P., and G. M. Walford. 1995. Major riparian vegetation types of eastern Wyoming. Submitted to Wyoming Department of Environmental Quality, Water Quality Division. Wyoming Natural Diversity Database, Laramie, WY. 245 pp.
- Kagan, J. 1997. Draft of Oregon and Washington vegetation report. Oregon Natural Heritage Program, Portland.
- Kearney, T. H., and R. H. Peebles, and collaborators. 1969. Arizona flora. University of California, Berkeley, CA. 1085 pp.
- Kittel, G. M. 1994. Montane vegetation in relation to elevation and geomorphology along the Cache la Poudre River, Colorado. Unpublished thesis, University of Wyoming, Laramie.
- Kittel, G. M., and N. D. Lederer. 1993. A preliminary classification of the riparian vegetation of the Yampa and San Miguel/Dolores river basins. Unpublished report prepared for Colorado Department of Health and the Environmental Protection Agency by The Nature Conservancy, Colorado Field Office, Boulder.
- Kittel, G., E. Van Wie, M. Damm, R. Rondeau, S. Kettler, and J. Sanderson. 1999a. A classification of the riparian plant associations of the Rio Grande and Closed Basin watersheds, Colorado. Unpublished report prepared by the Colorado Natural Heritage Program, Colorado State University, Fort Collins.
- Kittel, G., R. Rondeau, N. Lederer, and D. Randolph. 1994. A classification of the riparian vegetation of the White and Colorado River basins, Colorado. Final report submitted to Colorado Department of Natural Resources and the Environmental Protection Agency. Colorado Natural Heritage Program, Boulder. 166 pp.
- Kittel, G., R. Rondeau, and A. McMullen. 1996. A classification of the riparian vegetation of the Lower South Platte and parts of the Upper Arkansas River basins, Colorado. Submitted to Colorado Department of Natural Resources and the Environmental Protection Agency, Region VIII. Prepared by Colorado Natural Heritage Program, Fort Collins. 243 pp.
- Kittel, G., R. Rondeau, and S. Kettler. 1995. A classification of the riparian vegetation of the Gunnison River Basin, Colorado. Submitted to Colorado Department of Natural Resources and the Environmental Protection Agency. Prepared by Colorado Natural Heritage Program, Fort Collins. 114 pp.
- Kovalchik, B. L. 1987. Riparian zone associations - Deschutes, Ochoco, Fremont, and Winema national forests. Technical Paper 279-87. USDA Forest Service, Pacific Northwest Region, Portland, OR. 171 pp.
- Martin, W. C., and C. R. Hutchins. 1980. Flora of New Mexico. Volume 1. A. R. Strauss and Cramer, Germany. 1276 pp.
- Muldavin, E., P. Durkin, M. Bradley, M. Stuever, and P. Mehlhop. 2000a. Handbook of wetland vegetation communities of New Mexico. Volume I: Classification and community descriptions. Final report to the New Mexico Environment Department and the Environmental Protection Agency prepared by the New Mexico Natural Heritage Program, University of New Mexico, Albuquerque.
- Muldavin, E., P. Mehlhop, and E. DeBruin. 1994a. A survey of sensitive species and vegetation communities in the Organ Mountains of Fort Bliss. Volume III: Vegetation communities. Report prepared for Fort Bliss, Texas, by New Mexico Natural Heritage Program, Albuquerque.
- Muldavin, E., R. Wallace, and P. Mehlhop. 1993a. Riparian ecological site inventory for New Mexico Bureau Land Management lands. Final Report COOP Agreement F91070-0003, USDI Bureau of Land Management, New Mexico State Office, Santa Fe.
- Myhre, J., and E. A. Clements. 1972. A study of the flora of the islands and the shoreline of the Snake River between Grandview, Idaho, and Guffey Butte, Owyhee County, Idaho. Unpublished report prepared for Biology Department, College of Idaho, Caldwell. 18 pp.
- Padgett, W. G., A. P. Youngblood, and A. H. Winward. 1988b. Riparian community type classification of Utah. Publication R4-ECOL-88-01. USDA Forest Service, Forest and Range Experiment Station, Ogden, UT.
- Padgett, W. G., A. P. Youngblood, and A. H. Winward. 1989. Riparian community type classification of Utah and southeastern Idaho. Research Paper R4-ECOL-89-0. USDA Forest Service, Intermountain Forest and Range Experiment Station, Ogden, UT.
- Phillips, C. M. 1977. Willow carrs of the upper Laramie River Valley, Colorado. Unpublished thesis, Colorado State University, Fort Collins. 71 pp.
- Sawyer, J. O., and T. Keeler-Wolf. 1995. A manual of California vegetation. California Native Plant Society, Sacramento. 471 pp.
- Shelford, V. E. 1954. Some lower Mississippi Valley flood plain biotic communities: Their age and elevation. Ecology 35:1-14.
- Szaro, R. C. 1989. Riparian forest and scrubland community types of Arizona and New Mexico. Desert Plants Special Issue 9(3-4):70-139.
- Thompson, W. H., and P. L. Hansen. 2002. Classification and management of riparian and wetland sites of Alberta''s Grasslands Natural Region and adjacent subregions. Bitterroot Restoration, Inc., Cows and Fish, Lethbridge. 416 pp.
- Tuhy, J. S., and S. Jensen. 1982. Riparian classification for the Upper Salmon and Middle Fork Salmon River drainages, Idaho. Unpublished report prepared for the USDA Forest Service, Intermountain Region by White Horse Associates, Smithfield, UT. 183 pp.
- Vaghti, M. G. 2003. Riparian vegetation classification in relation to environmental gradients, Sacramento River, CA. Thesis, University of California, Davis.
- Weber, W. A. 1990. Colorado flora: Eastern slope. University Press of Colorado, Niwot, CO. 396 pp.
- Youngblood, A. P., W. G. Padgett, and A. H. Winward. 1985a. Riparian community type classification of eastern Idaho-western Wyoming. R4-Ecol-85-01. USDA Forest Service, Intermountain Region, Ogden, UT. 78 pp.