Print Report

A3254 Agropyron cristatum - Bromus inermis - Poa pratensis Ruderal Grassland Alliance

Type Concept Sentence: This alliance occurs in disturbed dry to mesic grasslands and meadows found in lowland, montane and subalpine elevations (sea level to 3600 m) throughout the western U.S. and Canada. Vegetation can be a monoculture of a single non-native graminoid species, or a mix of several non-native forbs and graminoids. Graminoids include Agropyron cristatum and Bromus inermis (which has been purposefully seeded to prevent soil erosion), as well as many introduced forage species, especially in more mesic montane uplands such as Alopecurus pratensis, Dactylis glomerata, Phleum pratense, Poa pratensis, and Psathyrostachys juncea. Highly invasive and wind- and animal-distributed non-native forb species include Sisymbrium altissimum, Descurainia sophia, and Lappula occidentalis.

Common (Translated Scientific) Name: Crested Wheatgrass - Smooth Brome - Kentucky Bluegrass Ruderal Grassland Alliance

Colloquial Name: Western Ruderal Perennial Grassland

Hierarchy Level:  Alliance

Type Concept: This alliance occurs in disturbed dry to mesic grasslands and meadows found in lowland, montane and subalpine elevations (sea level to 3600 m) throughout the western U.S. and Canada. Vegetation can be a monoculture of a single non-native graminoid species, or a mix of several non-native forbs and graminoids. Graminoids include Agropyron cristatum and Bromus inermis (which has been purposefully seeded to prevent soil erosion), as well as many introduced forage species, especially in more mesic montane uplands, such as Alopecurus pratensis, Dactylis glomerata, Phleum pratense, Poa pratensis, and Psathyrostachys juncea. Highly invasive and wind- and animal-distributed non-native forb species include Sisymbrium altissimum, Descurainia sophia, and Lappula occidentalis.

Diagnostic Characteristics: Dominant diagnostic species for this alliance are invasive, perennial grass species such as Agropyron cristatum, Alopecurus pratensis, Dactylis glomerata, Phleum pratense, Poa pratensis, Psathyrostachys juncea, and many others.

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Successful introductions of non-native forage species have created stands of late-seral grasslands that are difficult to restore to native species.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available

Floristics: Vegetation can be a monoculture of a single non-native graminoid species, or a mix of several non-native forbs and graminoids. Graminoids include Agropyron cristatum and Bromus inermis (which has been purposefully seeded to prevent soil erosion), as well as many introduced forage species, especially in more mesic montane uplands, such as Alopecurus pratensis, Dactylis glomerata, Phleum pratense, Poa pratensis, and Psathyrostachys juncea (= Elymus junceus). Highly invasive and wind- and animal-distributed non-native forb species include Sisymbrium altissimum, Descurainia sophia, and Lappula occidentalis.

Dynamics:  No Data Available
Environmental Description:  This alliance occurs in disturbed dry to mesic grasslands and meadows found in lowland, montane and subalpine elevations (sea level to 3600 m) throughout the western U.S. and Canada.
Geographic Range: This alliance occurs in lowland, montane and subalpine elevations (sea level to 3600 m) throughout the western U.S. and Canada.

Nations: CA,US

States/Provinces:  CO, ID, KS, MT, ND, NE, NV, SD, SK, UT, WY


Confidence Level: Low - Poorly Documented

Confidence Level Comments: No Data Available
Grank: GNA

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.90 Smooth Brome - Knapweed species - Pepperweed species Western North American Ruderal Grassland & Shrubland Macrogroup M493 2.B.2.Nf.90
Group 2.B.2.Nf.90.a Western North American Interior Ruderal Grassland & Shrubland Group G624 2.B.2.Nf.90.a
Alliance A3254 Crested Wheatgrass - Smooth Brome - Kentucky Bluegrass Ruderal Grassland Alliance A3254 2.B.2.Nf.90.a
Association CEGL005264 Smooth Brome - (Western Wheatgrass) Ruderal Grassland CEGL005264 2.B.2.Nf.90.a
Association CEGL005266 Crested Wheatgrass - (Western Wheatgrass, Needle-and-Thread) Ruderal Grassland CEGL005266 2.B.2.Nf.90.a
Association CEGL005471 Crested Wheatgrass - Cheatgrass Ruderal Grassland CEGL005471 2.B.2.Nf.90.a
Concept Lineage: A.3563

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: No Data Available
Concept Author(s): K.A. Schulz, in Faber-Langendoen et al. (2013)

Author of Description: K.A. Schulz

Acknowledgements: No Data Available

Version Date: 09-27-13
  • 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.