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CEGL001598 Danthonia californica Valley Grassland
Type Concept Sentence: No Data Available
Common (Translated Scientific) Name: California Oatgrass Valley Grassland
Colloquial Name: California Oatgrass Valley Grassland
Hierarchy Level: Association
Type Concept: This association is limited to the rainshadow of the eastern foothills of the Oregon Coast Range. The annual precipitation of the area is less than 100 cm, and summers are hot and dry. This community seems to prefer xeric, somewhat steep sites on south- or west-facing slopes. Soils are typically rocky, and elevations are between 150 and 370 m (490-1200 feet). This is a perennial grassland dominated by Danthonia californica which provides up to 70% cover. Several other perennial grasses may be present in small amounts such as Elymus glaucus, Koeleria macrantha and Festuca rubra. Annuals, such as Epilobium brachycarpum, Madia gracilis and Navarretia spp. may also be present in small amounts. Other perennials present may include Brodiaea coronaria, Fragaria vesca, Pteridium aquilinum, and Ranunculus occidentalis.
Diagnostic Characteristics: No Data Available
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: No Data Available
Floristics: This herbaceous association is strongly dominated by the cespitose perennial grass Danthonia californica, averaging 0.5 m in height and up to 70% cover. Several other perennial grasses are present in small amounts, such as Elymus glaucus, Koeleria macrantha, and Festuca rubra. Both annual and perennial forbs occur, none with high cover. Annuals include Epilobium brachycarpum, Madia gracilis, and Navarretia spp. Perennials include Brodiaea coronaria, Fragaria vesca, Pteridium aquilinum, and Ranunculus occidentalis. All known stands of this association have a significant component of introduced weedy species due to severe grazing, including annual and perennial forbs and grasses. Introduced grasses include Cynosurus echinatus, Bromus racemosus (= Bromus commutatus), Schedonorus arundinaceus (= Festuca arundinacea), and Holcus lanatus. Exotic forbs can include Plantago lanceolata and Daucus carota.
Dynamics: No Data Available
Environmental Description: This Danthonia californica association is found on the margins of the Willamette Valley, one of the warmest and driest regions of Oregon west of the Cascades. The climatic characteristics are due to the rainshadow effect of the Coast Ranges to the west, which results in annual precipitation of less than 100 cm (as compared to well over 200 cm on the coast). Summers in this valley are moderately hot and dry, with potential evapotranspiration far exceeding the moisture recharged during the wet, mild winters.
Little detailed information is available regarding the environmental parameters associated with this type. Topography is hilly to mountainous, with broad rolling tops and steep sideslopes. It occupies relatively xeric sites, such as somewhat steep to steep, south- or west-facing hills or slopes, at elevations of roughly 150-360 m. Soils are typically rocky and derived from colluvium and residuum of sedimentary or igneous rocks. They are well-drained, moderately deep to deep, and have textures of silty clays and gravelly silty clay loams.
Little detailed information is available regarding the environmental parameters associated with this type. Topography is hilly to mountainous, with broad rolling tops and steep sideslopes. It occupies relatively xeric sites, such as somewhat steep to steep, south- or west-facing hills or slopes, at elevations of roughly 150-360 m. Soils are typically rocky and derived from colluvium and residuum of sedimentary or igneous rocks. They are well-drained, moderately deep to deep, and have textures of silty clays and gravelly silty clay loams.
Geographic Range: This association occurs in scattered locations along the eastern foothills of the Oregon Coast Range in the Willamette Valley. May also be on a few (2-3 sites, all tiny) locations in the San Juan Islands of Washington, and in a few locations of interior valleys of California. It may be related to past grazing impacts.
Nations: US
States/Provinces: CA, OR, WA
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.684654
Confidence Level: Low
Confidence Level Comments: No Data Available
Grank: G1Q
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.4 Southern Vancouverian Lowland Grassland & Shrubland Macrogroup | M050 | 2.B.2.Nf.4 |
| Group | 2.B.2.Nf.4.a Manzanita species / Roemer''s Fescue - California Oatgrass Shrubland & Grassland Group | G488 | 2.B.2.Nf.4.a |
| Alliance | A4210 Roemer''s Fescue - California Oatgrass Interior Prairie, Bald & Bluff Grassland Alliance | A4210 | 2.B.2.Nf.4.a |
| Association | CEGL001598 California Oatgrass Valley Grassland | CEGL001598 | 2.B.2.Nf.4.a |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: > Danthonia californica - Eriophyllum lanatum (Chappell 2006b)
> Danthonia californica - Eriophyllum lanatum Association (Chappell 2006a) [8 plots]
? Danthonia californica (Sawyer et al. 2009) [41.050.05]
= Danthonia californica Valley Grassland (Kagan and Seyer 1982)
> Danthonia californica - Eriophyllum lanatum Association (Chappell 2006a) [8 plots]
? Danthonia californica (Sawyer et al. 2009) [41.050.05]
= Danthonia californica Valley Grassland (Kagan and Seyer 1982)
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- Chappell, C. B. 2006a. Plant associations of balds and bluffs of western Washington. Natural Heritage Report 2006-02. Washington Natural Heritage Program, Washington Department of Natural Resources, Olympia. [http://www.dnr.wa.gov/nhp/refdesk/communities/pdf/balds_veg.pdf]
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- Kagan, J. S. 1980. The biology of Lomatium bradshawii (Apiaceae), a rare plant of Oregon. Unpublished thesis, University of Oregon, Eugene.
- Kagan, J. S., J. A. Christy, M. P. Murray, and J. A. Titus. 2004. Classification of native vegetation of Oregon. January 2004. Oregon Natural Heritage Information Center, Portland. 52 pp.
- Kagan, J. S., and S. C. Seyer. 1982. Native grassland search in Willamette Valley, Oregon. Unpublished report to The Nature Conservancy, Portland, OR.
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- ORNHP [Oregon Natural Heritage Program]. No date. Unpublished data files. Oregon Natural Heritage Program, The Nature Conservancy, Portland, OR.
- 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.
- WNHP [Washington Natural Heritage Program]. 2018. Unpublished data files. Washington Natural Heritage Program, Department of Natural Resources, Olympia, WA.
- Western Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boulder, CO.