Selaginella bigelovii Herbaceous Alliance
Bushy spikemoss mats

USDA Ecological Section Map

Summary Information

  • Primary Life FormHerb
  • Elevation10-1200 m
  • State RarityS3
  • Global RarityG4
  • DistributionUSA: CA (NatureServe). Baja California, Mexico (TJM2)
  • Endemic to CaliforniaNo
  • Endemic to California Floristic Province and DesertsYes
  • Date Added2009/09/01

Characteristic Species

Selaginella bigelovii is dominant or conspicuous as rhizomatous mats in the herbaceous layer with Aira caryophyllea, Avena barbata, Bromus diandrus, Bromus rubens, Corethrogyne filaginifolia, Logfia filaginoides, Melica imperfecta, Mirabilis laevis var. crassifolia, Plantago erecta and Vulpia microstachys. Emergent shrubs may be present at low cover, including Adenostoma fasciculatum, Artemisia californica, Ceanothus crassifolius, Diplacus aurantiacus, Eriogonum fasciculatum, Eriogonum wrightii or Hesperoyucca whipplei.

Vegetation Layers

Herbs < 50 cm; cover is intermittent to continuous. Moss and lichens are usually present and may equal or exceed vascular plant cover.

Membership Rules

  • Selaginella bigelovii > 50% relative cover in the herbaceous layer; shrubs with open to sparse canopy at < 5-25% absolute cover (Evens and San 2005, Kittel et al. 2012).
  • Selaginella bigelovii in intermediate to dense mats on rocky outcrops and cliffs (Keeler-Wolf and Evens 2006).


Rock outcrops or skeletal soils over gently to steeply sloping, impervious substrates. Soils are sedimentary, granitic, or volcanic in origin.

Other Habitat, Alliance and Community Groupings

MCV (1995) California annual grassland series
NVCS (2009) Selaginella bigelovii herbaceous alliance
Calveg Barren, Annual grasses and forbs
Holland Diablan sage scrub, Native grassland
Munz Coastal sage scrub
WHR Barren, Coastal scrub
CDFW CA Code 42.062.00

National Vegetation Classification Hierarchy

Formation Class Lithomorphic Vegetation (Nonvascular and Sparse Vascular Rock Vegetation)
Formation Subclass Mediterranean, Temperate, and Boreal Nonvascular and Sparse Vegetation
Formation Mediterranean Cliff, Scree, and Rock Vegetation
Division Mediterranean California Cliff, Scree & Rock Vegetation
Macro Group California Cliff, Scree, and Other Rock Vegetation
Group Central California Coast Ranges cliff and canyon