Print Report
G796 Northern Rocky Mountain Lowland-Foothill Riparian Forest Group
Type Concept Sentence: This group contains riparian forests dominated by Populus balsamifera along major streams and rivers throughout the northwestern United States.
Common (Translated Scientific) Name: Northern Rocky Mountain Lowland-Foothill Riparian Forest Group
Colloquial Name: Northern Rocky Mountain Lowland-Foothill Riparian Forest
Hierarchy Level: Group
Type Concept: Vegetation within this group is characterized by an open to moderately dense tree layer that is dominated by Populus balsamifera ssp. trichocarpa and Populus balsamifera ssp. balsamifera. Tree associates include Populus deltoides, Populus angustifolia, Pinus ponderosa, and Picea spp. A shrub layer is usually present and may be dominated by Alnus incana, Betula papyrifera, Cornus sericea, Crataegus douglasii, Prunus virginiana, Ribes americanum, Salix exigua, and Symphoricarpos albus. The herbaceous layer is usually relatively sparse and is dominated by either forbs or graminoids. Common species include Actaea rubra, Cicuta douglasii, Equisetum sylvaticum, Mentha arvensis, and Symphyotrichum spathulatum. This riparian forest group occurs on alluvial terraces along major streams and rivers throughout the northwestern United States. It can occur on alluvial terraces of major streams and rivers, margins of lakes, meadows, deltas, river mouths, and terraces. Stands can occupy broad floodplains or form narrow stringers adjacent to streams with a much steeper slope. Soils typically overlay river gravel and/or cobbles and are coarse-textured. Water tables may drop below 1 m of the soil surface in summer, but can remain moist due to capillary action.
Diagnostic Characteristics: Stands dominated by Populus balsamifera ssp. trichocarpa or Populus balsamifera ssp. balsamifera.
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: No Data Available
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: This group is characterized by a tall (<25 m) broad-leaved deciduous tree. The canopy is moderately dense with 50-80% cover on average, but in some stands can total over 90%. The tall- and short-shrub layers vary between 10-50% cover. The forb layer is sparse with up to 20% cover. Ferns can dominate the herbaceous layer with up to 40% cover. Graminoids can be dominant in some stands (particularly recently disturbed ones), or can be sparse.
Floristics: This group is dominated by Populus balsamifera ssp. trichocarpa and/or Populus balsamifera ssp. balsamifera. Other trees present may include Populus deltoides, Populus angustifolia, Pinus ponderosa, and Picea spp. and can occur in the canopy with Populus balsamifera in Montana stands. The shrub layer is dominated by Alnus incana, Betula papyrifera, Cornus sericea, Prunus virginiana, and Ribes americanum. The forb layer can be dominated by Actaea rubra, Mentha arvensis, and Symphyotrichum spathulatum (= Aster occidentalis). The graminoid cover is usually less than 10%, but can be up to 80%, and mainly consists of introduced hay grasses. Equisetum sylvaticum can dominate the fern layer with up to 40% cover.
Dynamics: Populus species are dependent on flooding for successful sexual reproduction.
Environmental Description: This group occurs on alluvial terraces along major streams and rivers. It can occur on alluvial terraces of major streams and rivers, margins of lakes, meadows, deltas, river mouths, and terraces. Stands can occupy broad floodplains (1-3% slopes) or form narrow stringers adjacent to streams with a much steeper slope (10-15%). Soils are typically Entisols, usually up to 1 m of mineral soil overlying river gravel and/or cobbles. Soil texture varies from loam to coarse sand. Water tables usually drop below 1 m of the soil surface in summer, but can remain moist due to capillary action. A fluctuating water table in these soils is evidenced by the common presence of mottles.
Geographic Range: This group is found throughout the northern Interior West from the foothills of the Sierra Nevada to Montana, and from southern British Columbia to Nevada, Utah and western Wyoming.
Nations: CA,US
States/Provinces: AB, BC, CA, ID, MT, NV, OR, UT, WA, WY
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.932908
Confidence Level: Moderate
Confidence Level Comments: No Data Available
Grank: GNR
Greasons: No Data Available
| Type | Name | Database Code | Classification Code |
|---|---|---|---|
| Class | 1 Forest & Woodland Class | C01 | 1 |
| Subclass | 1.B Temperate & Boreal Forest & Woodland Subclass | S15 | 1.B |
| Formation | 1.B.3 Temperate Flooded & Swamp Forest Formation | F026 | 1.B.3 |
| Division | 1.B.3.Nc Rocky Mountain-Great Basin Montane Flooded & Swamp Forest Division | D195 | 1.B.3.Nc |
| Macrogroup | 1.B.3.Nc.1 Engelmann Spruce - Narrowleaf Cottonwood / Red-osier Dogwood Riparian & Swamp Forest Macrogroup | M034 | 1.B.3.Nc.1 |
| Group | 1.B.3.Nc.1.c Northern Rocky Mountain Lowland-Foothill Riparian Forest Group | G796 | 1.B.3.Nc.1.c |
| Alliance | A0311 Black Cottonwood Northern Rocky Mountain Riparian Forest Alliance | A0311 | 1.B.3.Nc.1.c |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: No Data Available
- Faber-Langendoen, D., J. Drake, S. Gawler, M. Hall, C. Josse, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, L. Sneddon, K. Schulz, J. Teague, M. Russo, K. Snow, and P. Comer, editors. 2010-2019a. Divisions, Macrogroups and Groups for the Revised U.S. National Vegetation Classification. NatureServe, Arlington, VA. plus appendices. [in preparation]