Deschampsia cespitosa - Hordeum brachyantherum - Danthonia californica Herbaceous Alliance
Coastal tufted hair grass - Meadow barley - California oatgrass meadow

USDA Ecological Section Map

Summary Information

  • Primary Life FormHerb
  • Elevation0-1500 m
  • State RarityS3
  • Global RarityGNR
  • DistributionCAN: BC. USA: CA, OR, WA (NatureServe)
  • Endemic to CaliforniaNo
  • Endemic to California Floristic Province and DesertsNo
  • Date Added2020/01/31

Characteristic Species

Deschampsia cespitosa or Hordeum brachyantherum is dominant or co-dominant in the herbaceous layer with Achillea millefolium, Agrostis stolonifera, Aira caryophyllea, Anthoxanthum odoratum, Argentina egedii, Carex spp., Cirsium vulgare, Danthonia californica, Deschampsia danthonioides, Distichlis spicata, Eleocharis acicularis, Eleocharis macrostachya, Epilobium ciliatum, Eryngium armatum, Holcus lanatus, Horkelia marinensis, Hypochaeris radicata, Iris douglasiana, Juncus arcticus, Juncus phaeocephalus, Lilaeopsis masonii, Lolium perenne, Lotus spp., Lupinus versicolor, Medicago polymorpha, Plantago lanceolata, Potentilla gracilis, Ranunculus californicus, Ranunculus flammula, Rumex acetosella, Senecio hydrophiloides, Sisyrinchium bellum, Trifolium spp. and Triglochin striata. Emergent shrubs may be present at low cover, including Baccharis pilularis, Rosa nutkana, Rubus spp. and Rubus ursinus.

Vegetation Layers

Herbs < 1 m; cover is continuous.

Membership Rules

  • Deschampsia caespitosa > 50% relative cover in the herbaceous layer; Baccharis pilularis ≤ 20% absolute cover, and no taller than the tallest grasses (Keeler-Wolf et al. 2003a).
  • Deschampsia cespitosa, Iris douglasiana, and/or Eryngium armatum has > 30% relative cover with other wet meadow herbs; if Holcus lanatus has highest cover, these native species may have as low as 10% combined cover (Buck-Diaz et al. 2021).
  • Hordeum brachyantherum > 30% relative cover in the herbaceous layer (Buck-Diaz et al. 2021, Evens and Kentner 2006).
  • Hordeum brachyantherum is characteristically present, usually with other wetland plants that may be at high cover (Klein et al. 2007).
  • Deschampsia cespitosa, Danthonia californica, Iris douglasiana, and/or Eryngium armatum > 30% relative cover individually or share > 50% relative cover in the herbaceous layer (Buck-Diaz et al. 2021, Sikes et al. 2021, Sikes et al. 2023).
  • Hordeum brachyantherum > 30% relative cover with Achillea millefolium, Distichlis spicata, Holcus lanatus, Hordeum marinum, Lolium perenne, and/or Lotus corniculatus in the herbaceous layer (Sikes et al. 2023).

Habitats

Moist to wet meadows on coastal bluffs, coastal terrace prairies, swales, stream terraces, sand dunes, and seasonally flooded areas. Soils are typically derived from alluvium, but can be slightly alkaline to moderately saline. The USFWS Wetland Inventory (2012 national list) recognizes Deschampsia cespitosa and Hordeum brachyantherum as FACW plants.

Other Habitat, Alliance and Community Groupings

MCV (1995) Tufted hair grass series
NVCS (2009) Deschampsia caespitosa saturated herbaceous alliance, Deschampsia caespitosa seasonally flooded herbaceous alliance, Deschampsia caespitosa temporarily flooded herbaceous alliance, Deschampsia caespitosa tidal herbaceous alliance, Hordeum brachyantherum temporarily flooded herbaceous alliance
Calveg Wet grasses and forbs
Holland Coastal terrace prairie, Freshwater seep, Freshwater marsh, Coastal and valley freshwater marsh
Munz Coastal prairie, Freshwater marsh
WHR Fresh emergent wetland, Perennial grassland, Wet meadow
CDFW CA Code 41.221.00

National Vegetation Classification Hierarchy

Formation Class Mesomorphic Shrub and Herb Vegetation (Shrubland and Grassland)
Formation Subclass Temperate and Boreal Shrubland and Grassland
Formation Temperate and Boreal Freshwater Marsh
Division Western North American Freshwater Marsh
Macro Group Western North American Freshwater Marsh
Group Vancouverian coastal/tidal marsh and meadow