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CEGL005314 Quercus douglasii / Mixed Herbaceous Woodland

Type Concept Sentence: No Data Available

Common (Translated Scientific) Name: Blue Oak / Mixed Herbaceous Woodland

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This open to shaded woodland occurs across a wide range of elevations, between 30 and 1676 m (100-5500 feet), on moderate to steep slopes of all aspects, from bottom to upper slopes and ridgetops. The surface topography is variable, and soils are mostly sandy loam, but can be a wide variety of textures, including clay, clay loam, silt, silt loam, and sand. The vegetation is an overstory tree layer dominated by Quercus douglasii. A shrub layer is absent, although a few scattered individuals and even clumps of shrubs may occur. The herbaceous cover is typically the predominant undergrowth cover in this type and typically composed of a high cover of grasses (average 90%). However, no one species or suite of species are present in all stands. Commonly encountered native grass species include Elymus glaucus, Leymus triticoides, Melica californica, Nassella pulchra, Poa secunda, and Vulpia microstachys. Introduced grasses commonly include Avena barbata, Bromus diandrus, Bromus hordeaceus, Bromus rubens, Brachypodium distachyon, and Cynosurus echinatus. Forb species vary depending on yearly rainfall and are highly diverse.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Borchert et al. (1993a) types are more finely divided, taking into account the wide variation of forb or grass species dominance that can change year to year depending on the amount of rainfall and the seasonality of that rainfall.

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

Floristics: In this association, Quercus douglasii is the dominant overstory tree. A wide variety of trees may be present, depending on the elevation and neighboring vegetation. Allen et al. (1989) (298 sampled stands of this type) list 16 tree species with less than 15% constancy. These include Aesculus californica, Juglans californica, Pinus contorta, Pinus coulteri, Pinus jeffreyi, Pinus ponderosa, Pinus sabiniana, Pseudotsuga menziesii, Quercus agrifolia, Quercus chrysolepis, Quercus dumosa, Quercus garryana, Quercus kelloggii, Quercus lobata, Quercus x morehus, and Quercus wislizeni. Stands in the central interior coast have Pinus sabiniana and Quercus lobata as occasional co-associates. The shrub layer is generally poorly represented, and a wide variety of shrub species may occur in low cover (occasionally high cover), but then the herbaceous cover is very high. Allen et al. (1989) recorded many shrubs that occur with less than 15% constancy. These include Adenostoma fasciculatum, Arctostaphylos canescens, Arctostaphylos manzanita, Arctostaphylos virgata, Cercocarpus montanus var. glaber (= Cercocarpus betuloides), Ceanothus integerrimus, Eriodictyon californicum, Eriogonum fasciculatum, Ericameria linearifolia (= Haplopappus linearifolius), Heteromeles arbutifolia, Lonicera interrupta, Lonicera subspicata, Lupinus albifrons, Prunus ilicifolia, Frangula californica (= Rhamnus californica), Rhamnus crocea, Toxicodendron diversilobum (= Rhus diversiloba), Rhus trilobata, Ribes californicum, Ribes quercetorum, Salvia apiana, Salvia leucophylla, Salix spp., and Xylococcus bicolor. Additional shrub species from other studies include Arctostaphylos pungens, Artemisia californica, Ericameria nauseosa (= Chrysothamnus nauseosus), Sambucus nigra ssp. cerulea (= Sambucus mexicana), and Symphoricarpos albus. Non-native grasses Bromus diandrus, Bromus hordeaceus, Bromus rubens, Avena barbata, and Cynosurus echinatus may be abundant (0-100% cover, average 90%), though a variety of native grasses often occur such as Elymus glaucus, Leymus triticoides, Melica californica, Nassella pulchra, Poa secunda, and Vulpia microstachys. Forb species vary depending on yearly rainfall and are highly diverse.

Dynamics:  No Data Available
Environmental Description:  This open to shaded woodland occurs across a wide range of elevations, between 30 and 1676 m (100-5500 feet), on moderate to steep slopes of all aspects, from bottom to upper slopes and ridgetops. The surface topography is variable, and soils are mostly sandy loam, but can be a wide variety of textures, including clay, clay loam, silt, silt loam, and sand.
Geographic Range: This association has a widespread occurrence ringing the Central Valley of California. It occurs along the central coast from Monterey to Santa Barbara counties, the north-central coast from Sonoma to Contra Costa counties, and in the foothills of the Sierra Nevada from Shasta to Mariposa counties (Allen et al. 1989, Klein et al. 2007). It is also documented in the interior coastal ranges of San Benito County (Pinnacles National Monument) (Evens et al. 2006).

Nations: US

States/Provinces:  CA


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.1 Warm Temperate Forest & Woodland Formation F018 1.B.1
Division 1.B.1.Nc Californian Forest & Woodland Division D007 1.B.1.Nc
Macrogroup 1.B.1.Nc.1 California Live Oak - California Laurel - Western Cypress species Forest & Woodland Macrogroup M009 1.B.1.Nc.1
Group 1.B.1.Nc.1.a California Live Oak - Valley Oak - California Laurel Forest & Woodland Group G195 1.B.1.Nc.1.a
Alliance A3348 Blue Oak - California Foothill Pine Woodland Alliance A3348 1.B.1.Nc.1.a
Association CEGL005314 Blue Oak / Mixed Herbaceous Woodland CEGL005314 1.B.1.Nc.1.a
Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: > Quercus douglasii / Amsinckia intermedia - Plagiobothrys nothofulvus (Borchert et al. 1993a)
> Quercus douglasii / Cercocarpus betuloides / Bowlesia incana - Lithophragma affine (Borchert et al. 1993a)
> Quercus douglasii / Collinsia sparsiflora - Rigiopappus leptocladus (Borchert et al. 1993a)
> Quercus douglasii / Delphinium parryi - Phacelia imbricata (Borchert et al. 1993a)
> Quercus douglasii / Eriogonum elongatum / Lotus subpinnatus - Plantago erecta (Borchert et al. 1993a)
> Quercus douglasii / Erodium moschatum - Hordeum leporinum (Borchert et al. 1993a)
> Quercus douglasii / Euphorbia spathulata - Pentagramma triangularis (Borchert et al. 1993a)
> Quercus douglasii / Galium andrewsii - Lupinus concinnus (Borchert et al. 1993a)
> Quercus douglasii / Hordeum leporinum - Viola pedunculata (Borchert et al. 1993a)
> Quercus douglasii / Lotus subpinnatus - Stipa pulchra (Borchert et al. 1993a)
> Quercus douglasii / Lupinus concinnus - Trifolium ciliolatum (Borchert et al. 1993a)
> Quercus douglasii / Ribes californicum / Bromus diandrus (Borchert et al. 1993a)
> Quercus douglasii / Annual Grass - Forb (Klein et al. 2007)
= Quercus douglasii / Mixed Herbaceous Woodland (Kittel et al. 2012a)
> Quercus douglasii / Perennial Grass - Forb (Klein et al. 2007)
= Blue Oak / Grass (Allen et al. 1989)
Concept Author(s): G. Kittel et al. (2012a)

Author of Description: G. Kittel and J. Evens

Acknowledgements: No Data Available

Version Date: 09-24-07
  • Allen, B. H., R. R. Evett, B. A. Holzman, and A. J. Martin. 1989. Report on rangeland cover type description for California hardwood rangelands. Department of Forestry and Fire Protection and Department of Forestry and Resource Management. Berkeley, CA.
  • Borchert, M., H. Gordon, and T. White. 1993a. Preliminary definitions of Transverse and Peninsular Range series and association. Unpublished report. USDA Forest Service, Los Padres National Forest, Goleta, CA.
  • Evens, J., A. Klein, J. Taylor, T. Keeler-Wolf, and D. Hickson, principal investigators. 2006. Vegetation classification, descriptions, and mapping of the Clear Creek Management Area, Joaquin Ridge, Monocline Ridge, and Environs in San Benito and western Fresno counties, California. Final report prepared by California Native Plant Society and California Department of Fish and Game, Sacramento, CA. 273 pp.
  • Kittel, G., E. Reyes, J. Evens, J. Buck, and D. Johnson. 2012a. Vegetation classification and mapping project report, Pinnacles National Monument. Natural Resource Report NPS/SFAN/NRR-2012/574. National Park Service, Fort Collins, CO. 428 pp.
  • Klein, A., J. Crawford, J. Evens, T. Keeler-Wolf, and D. Hickson. 2007. Classification of the vegetation alliances and associations of the northern Sierra Nevada foothills, California. Volumes 1 and 2. Report prepared for California Department of Fish and Game, Habitat Conservation Division. California Native Plant Society, Sacramento, CA. [https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=18232&inline=1]
  • Western Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boulder, CO.