Print Report

CEGL002916 Bromus diandrus - Avena spp. Ruderal Grassland

Type Concept Sentence: Bromus diandrus is characteristically present in the herbaceous layer and usually codominates with Avena fatua or Avena barbata. This association is only sampled from the Santa Monica Mountains region and the Channel Islands but is anecdotally known from much of cismontane California.

Common (Translated Scientific) Name: Ripgut Brome - Oat species Ruderal Grassland

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This association is only sampled from the Santa Monica Mountains region and the Channel Islands. However, it is anecdotally known from much of cismontane California. This herbaceous association occurs on gentle to somewhat steep slopes of variable aspect at elevations between 15 and 550 m. Bromus diandrus is characteristically present in the herbaceous layer and usually codominates with Avena fatua or Avena barbata. Brassica nigra is also usually found in this layer at low cover. Hazardia squarrosa, Artemisia californica, and Lotus scoparius are occasionally found in the shrub layer at low cover, and Quercus lobata infrequently occurs in the tree layer at low cover.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Of all the California annual grasslands dominated by non-native annual grasses, those with Avena sp. and mixes of other species tend to have a higher proportion of native annuals. However, indication from this data set suggests that any given native herbaceous species tends to occur in only 20% or less of the stands.

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

Floristics: Stands of this association at Santa Monica Mountains National Recreation Area form an open to intermittent herbaceous layer (10-65%, mean 43.9%) at 0.01-1 m tall. The shrub layer is sparse to open (0-9%, mean 2.4%) at 0-5 m tall. Trees are infrequently emergent (0-1% cover, mean 0.1%) with hardwoods at 0-10 m tall. Total vegetation cover is 13-70%; mean cover is 46.3%. Bromus diandrus is characteristically present and codominant with either Avena fatua or Avena barbata. Brassica nigra is usually included in this layer at low cover, while Bromus madritensis, Bromus hordeaceus, and Marrubium vulgare are occasionally present. Other forbs are occasionally present and sometimes abundant, such as Erodium botrys and Centaurea melitensis. The shrub layer sometimes includes Hazardia squarrosa, Artemisia californica, and Lotus scoparius. The tree layer infrequently includes Quercus lobata as an emergent.

Dynamics:  Until further inventory is completed, there is no global information.
Environmental Description:  Until further inventory is completed, there is no global information.
Geographic Range: This association is only sampled from the Santa Monica Mountains region and the Channel Islands. However, it is anecdotally known from much of cismontane California.

Nations: US

States/Provinces:  CA


Confidence Level: Low

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.1 Mediterranean Scrub & Grassland Formation F038 2.B.1
Division 2.B.1.Na Californian Scrub & Grassland Division D327 2.B.1.Na
Macrogroup 2.B.1.Na.90 Wild Oat - Black Mustard - Ripgut Brome Ruderal Grassland, Meadow & Scrub Macrogroup M046 2.B.1.Na.90
Group 2.B.1.Na.90.a Wild Oat - Ripgut Brome Ruderal Grassland, Meadow & Scrub Group G497 2.B.1.Na.90.a
Alliance A3870 Wild Oat - Brome species Ruderal Annual Grassland Alliance A3870 2.B.1.Na.90.a
Association CEGL002916 Ripgut Brome - Oat species Ruderal Grassland CEGL002916 2.B.1.Na.90.a
Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: = Bromus diandrus - Avena spp. (Sawyer et al. 2009) [42.026.22]
= Bromus diandrus - Avena spp. Semi-natural Association (Rodriguez et al. 2017)
= Bromus diandrus-Avena spp. Herbaceous Association (Keeler-Wolf and Evens 2006)
< California Annual Grassland (Sawyer and Keeler-Wolf 1995)
< Non-native Grassland (#42200) (Holland 1986b)
Concept Author(s): T. Keeler-Wolf and J. Evens (2006)

Author of Description: T. Keeler-Wolf and J. Evens

Acknowledgements: No Data Available

Version Date: 08-24-16
  • CNPS [California Native Plant Society]. 2015b. Inventory of Rare and Endangered Plants (online edition, v8-02). Rare Plant Program, California Native Plant Society, Sacramento, CA. [http://www.rareplants.cnps.org].
  • Holland, R. F. 1986b. Preliminary descriptions of the terrestrial natural communities of California. Unpublished report prepared for the California Department of Fish and Game, Nongame-Heritage Program and Natural Diversity Database, Sacramento. 156 pp.
  • Keeler-Wolf, T., and J. Evens. 2006. Vegetation classification of the Santa Monica Mountains National Recreation Area and environs in Ventura and Los Angeles counties, California. A report submitted to National Park Service, Santa Monica Mountains National Recreation Area by California Department of Fish and Game, Wildlife and Habitat Data Analysis Branch and The California Native Plant Society, Vegetation Program, Sacramento, CA.
  • Rodriguez, D., K. G. Sikes, T. Keeler-Wolf, G. Kittel, J. Curtis, C. Curley, and J. Evens. 2017. Vegetation classification of Channel Islands National Park. Report to the National Park Service, Fort Collins, CO.
  • Sawyer, J. O., T. Keeler-Wolf, and J. Evens. 2009. A manual of California vegetation. Second edition. California Native Plant Society, Sacramento CA. 1300 pp.
  • Sawyer, J. O., and T. Keeler-Wolf. 1995. A manual of California vegetation. California Native Plant Society, Sacramento. 471 pp.
  • Western Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boulder, CO.