Key to Shrublands in California
- 1.
Shrublands in cismontane California or on desert margins. Total plant cover is commonly >20% to 100%; shrubs typically dominant; trees absent or of low cover (<10% cover)
- 2.
Shrubs with sclerophyllous, evergreen-leaved leaves dominant; stands from coast to desert margin and up to subalpine elevations—chaparral
- 3.
Stands broadly distributed in the state; however, not at the desert edge, on serpentine substrates, on infertile soils of coastal fog belt, or in the mountains
- 4.
Stands of dry exposed ridges and slopes; shrubs obligate seeders, facultative seeders, or sprouters
- 5.
An Adenostoma species strongly dominant alone or co-dominant with a coastal shrub species
- Adenostoma fasciculatum alliance
- Adenostoma fasciculatum — Salvia spp. alliance
- Adenostoma sparsifolium alliance
- Xylococcus bicolor alliance
- 5′.
A manzanita, ceanothus or other chaparral species dominant, co-dominant with Adenostoma, or co-dominant with other species
- 6.
A manzanita dominant or co-dominant
- Arctostaphylos (canescens, manzanita, stanfordiana) alliance
- Arctostaphylos (crustacea, tomentosa) alliance
- Arctostaphylos glandulosa alliance
- Arctostaphylos glauca alliance
- Arctostaphylos myrtifolia alliance
- Arctostaphylos viscida alliance
- 6′.
A ceanothus or other species dominant, co-dominant or diagnostically present
- Ceanothus (oliganthus, tomentosus) alliance
- Ceanothus cordulatus — Ceanothus integerrimus alliance
- Ceanothus crassifolius alliance
- Ceanothus cuneatus alliance
- Ceanothus greggii — Fremontodendron californicum alliance
- Ceanothus leucodermis alliance
- Ceanothus megacarpus alliance
- Ceanothus papillosus alliance
- Lotus scoparius — Lupinus albifrons — Eriodictyon spp. alliance
- Quercus berberidifolia alliance
- Xylococcus bicolor alliance
- 4′.
Stands usually on sheltered northward-facing slopes or concavities or higher slope positions; shrubs are mostly sprouters
- 7.
A scrub oak dominant or co-dominant
- Quercus berberidifolia alliance
- Quercus john-tuckeri alliance
- Quercus palmeri alliance
- Quercus wislizeni — Quercus chrysolepis (shrub) alliance
- 7′.
Shrubs other than a shrub oak dominant or co-dominant
- Arctostaphylos (canescens, manzanita, stanfordiana) alliance
- Arctostaphylos (nummularia, sensitiva) — Chrysolepis chrysophylla alliance
- Arctostaphylos glandulosa alliance
- Arctostaphylos pungens — Arctostaphylos pringlei alliance
- Ceanothus (oliganthus, tomentosus) alliance
- Ceanothus leucodermis alliance
- Ceanothus megacarpus alliance
- Cercocarpus montanus alliance
- Prunus ilicifolia — Heteromeles arbutifolia — Ceanothus spinosus alliance
- Xylococcus bicolor alliance
- 3′.
Stands regionally or locally restricted to drier desert margins, desert mountains, serpentine substrates, infertile soils of coastal fog belt, or mid- to high-elevations
- 8.
Stands along the desert margin of the Peninsular, Transverse, or Tehachapi ranges, or stands in the drier portions of the South Coast and the inner Central Coast ranges—semi-desert chaparral
- Adenostoma fasciculatum alliance
- Adenostoma sparsifolium alliance
- Arctostaphylos (nummularia, sensitiva) — Chrysolepis chrysophylla alliance
- Ceanothus greggii — Fremontodendron californicum alliance
- Quercus cornelius-mulleri alliance
- Quercus john-tuckeri alliance
- Quercus palmeri alliance
- Rhus ovata alliance
- 8′.
Stands restricted to serpentine, to the coastal fog belt, or in the mountains where snow is the main form of precipitation
- 9.
Stands restricted to serpentine substrates—serpentine chaparral
- Adenostoma fasciculatum alliance
- Arctostaphylos (bakeri, montana) alliance
- Arctostaphylos glauca alliance
- Arctostaphylos viscida alliance
- Frangula californica — Rhododendron occidentale — Salix breweri alliance
- Quercus durata alliance
- 9′.
Stands in the coastal fog belt or in the mountains where snow in the main form of precipitation
- 10.
Stands restricted to sandstone, siltstone, shale and other nutrient-poor sediments, and usually influenced by coastal fog, often in small patches—maritime chaparral
- 11.
Stands with a manzanita species usually dominant or co-dominant
- Arctostaphylos (canescens, manzanita, stanfordiana) alliance
- Arctostaphylos (crustacea, tomentosa) alliance
- Arctostaphylos (nummularia, sensitiva) — Chrysolepis chrysophylla alliance
- Arctostaphylos (purissima, rudis) special stands
- Arctostaphylos hookeri alliance
- Arctostaphylos hooveri alliance
- Arctostaphylos montereyensis provisional alliance
- Arctostaphylos morroensis alliance
- Arctostaphylos myrtifolia alliance
- Arctostaphylos pajaroensis alliance
- Arctostaphylos pumila provisional alliance
- 11′.
Stands with another species dominant
- Adenostoma fasciculatum alliance
- Baccharis pilularis alliance
- Ceanothus papillosus alliance
- Ceanothus verrucosus provisional alliance
- Malosma laurina alliance
- Quercus dumosa — Quercus pacifica alliance
- Rhus integrifolia alliance
- 10′.
Stands found in montane and subalpine elevations—montane chaparral
- Arctostaphylos patula — Arctostaphylos nevadensis alliance
- Ceanothus cordulatus — Ceanothus integerrimus alliance
- Ceanothus velutinus alliance
- Cercocarpus ledifolius alliance
- Chrysolepis sempervirens alliance
- Notholithocarpus densiflorus ssp. echinoides alliance
- Quercus sadleriana alliance
- Quercus vacciniifolia alliance
- 2′.
Shrubs with soft-leaved leaves dominant; the leaves drought-deciduous, winter-deciduous, or other evergreen, but not sclerophyllous; stands from coast to desert and up to alpine elevations—coastal, desert, mountain, and riparian scrubs
- 12.
Shrubs in coastal fens or in montane to alpine wet meadows or fens; leaves evergreen soft-leaved, or winter-deciduous; dominant plants usually sub-shrubs or dwarf-shrubs
- Cassiope mertensiana provisional alliance
- Dasiphora fruticosa alliance
- Kalmia microphylla provisional alliance
- Phyllodoce breweri alliance
- Phyllodoce empetriformis provisional alliance
- Rhododendron columbianum alliance
- Salix nivalis provisional alliance
- Salix petrophila alliance
- Vaccinium cespitosum alliance
- Vaccinium uliginosum alliance
- 12′.
Shrubs at low elevations not in fens or in wet montane meadows; leaves soft-leaved, drought-deciduous, winter-deciduous, or evergreen
- 13.
Evergreen shrubs predominating, but leaves not brittle or hardened with a waxy cuticle; stands usually of mesic, coastal, or recently disturbed settings—evergreen scrubs
- Baccharis pilularis alliance
- Ceanothus thyrsiflorus alliance
- Lotus scoparius — Lupinus albifrons — Eriodictyon spp. alliance
- Lupinus arboreus alliance
- Lupinus chamissonis — Ericameria ericoides alliance
- Venegasia carpesioides alliance
- 13′.
Drought-deciduous or winter-deciduous shrubs predominating; settings various
- 14.
Stands dominated by drought-deciduous or facultatively drought-deciduous shrubs; stands coastal or inland of cool to warm and dry exposures—coastal sage scrub, coastal succulent scrub, and other scrubs
- 15.
Stands with a buckwheat, sage, or sagebrush dominant to co-dominant
- Adenostoma fasciculatum — Salvia spp. alliance
- Artemisia californica — (Salvia leucophylla) alliance
- Cercocarpus montanus alliance
- Coreopsis gigantea alliance
- Deinandra clementina — Eriogonum giganteum provisional alliance
- Encelia californica — Eriogonum cinereum alliance
- Eriogonum arborescens — Eriogonum grande alliance
- Eriogonum fasciculatum alliance
- Eriogonum fasciculatum — Salvia apiana alliance
- Eriogonum wrightii — Eriogonum heermannii — Buddleja utahensis alliance
- Opuntia littoralis — Opuntia oricola — Cylindropuntia prolifera alliance
- Rhus integrifolia alliance
- Salvia apiana alliance
- Salvia mellifera — (Artemisia californica) alliance
- 15′.
Stands with other species dominant to co-dominant
- Cytisus scoparius — Genista monspessulana — Cotoneaster spp. semi-natural alliance
- Coreopsis gigantea alliance
- Deinandra clementina — Eriogonum giganteum provisional alliance
- Diplacus aurantiacus alliance
- Encelia californica — Eriogonum cinereum alliance
- Encelia farinosa alliance
- Ericameria linearifolia — Cleome isomeris alliance
- Ericameria palmeri provisional alliance
- Gutierrezia californica provisional alliance
- Hazardia squarrosa alliance
- Isocoma menziesii alliance
- Keckiella antirrhinoides alliance
- Lotus scoparius — Lupinus albifrons — Eriodictyon spp. alliance
- Lycium californicum provisional alliance
- Malacothamnus fasciculatus — Malacothamnus spp. alliance
- 14′.
Stands dominated by winter-deciduous shrubs; various settings
- 16.
Stands of moist coastal to wet settings, including riparian and bottomland settings
- 17.
Stands typical of moist coastal, low-elevation riparian—low-elevation riparian and mesic scrub
- 18.
Stands with a baccharis or willow dominant or diagnostically present
- Baccharis emoryi — Baccharis sergiloides alliance
- Baccharis pilularis alliance
- Baccharis salicifolia alliance
- Frangula californica — Rhododendron occidentale — Salix breweri alliance
- Salix exigua alliance
- Salix hookeriana — Salix sitchensis — Spiraea douglasii alliance
- Salix lasiolepis alliance
- 18′.
Stands with other species dominant or diagnostically present
- Cephalanthus occidentalis alliance
- Cornus sericea alliance
- Corylus cornuta var. californica alliance
- Frangula californica — Rhododendron occidentale — Salix breweri alliance
- Gaultheria shallon — Rubus (ursinus) alliance
- Lepidospartum squamatum alliance
- Pluchea sericea alliance
- Rhododendron columbianum alliance
- Rhus trilobata — Crataegus rivularis — Forestiera pubescens alliance
- Rosa californica alliance
- Rubus armeniacus — Sesbania punicea — Ficus carica semi-natural alliance
- Rubus spectabilis — Morella californica alliance
- Tamarix spp. semi-natural alliance
- Toxicodendron diversilobum alliance
- 17′.
Stands typical of montane riparian or other wetland settings—mountain riparian scrub
- 19.
Stands with a willow dominant or co-dominant
- Salix boothii — Salix geyeriana — Salix lutea alliance
- Salix eastwoodiae alliance
- Salix jepsonii alliance
- Salix lasiolepis alliance
- Salix lemmonii alliance
- Salix nivalis provisional alliance
- Salix orestera alliance
- Salix petrophila alliance
- Salix planifolia provisional alliance
- 19′.
Stands with a another species dominant
- Acer glabrum provisional alliance
- Alnus incana alliance
- Alnus viridis provisional alliance
- Artemisia cana alliance
- Betula glandulosa provisional alliance
- Betula occidentalis alliance
- Cornus sericeaalliance
- Cornus sericea — Rosa woodsii — Ribes spp. provisional alliance
- Dasiphora fruticosa alliance
- 16′.
Stands of mesic and drier upland settings, including rocky sites—upland deciduous scrub
- Acer glabrum provisional alliance
- Ceanothus integerrimus alliance
- Ephedra nevadensis — Lycium andersonii — Grayia spinosa alliance
- Prunus emarginata — Holodiscus discolor alliance
- Prunus virginiana provisional alliance
- Quercus garryana (shrub) alliance
- Rhus trilobata — Crataegus rivularis — Forestiera pubescens alliance
- Ribes quercetorum provisional alliance
- Prunus fasciculata — Salazaria mexicana alliance
- Toxicodendron diversilobum alliance
- 1′.
Shrublands in transmontane California; total plant cover is commonly <20% and as low as 2%; shrubs typically dominant; trees absent or of low cover, and occasionally perennial grasses will have similar or higher cover than shrubs
- 20.
Stands of the cool deserts including the Great Basin, Modoc Plateau, Mono Basin, and higher desert mountains—shrub-steppe
- 21.
Stands with a sagebrush or ephedra species dominant
- Artemisia arbuscula ssp. arbuscula alliance
- Artemisia cana alliance
- Artemisia nova alliance
- Artemisia rothrockii alliance
- Artemisia tridentata alliance
- Artemisia tridentata ssp. vaseyana alliance
- Ephedra californica — Ephedra trifurca alliance
- Ephedra funerea alliance
- Ephedra nevadensis — Lycium andersonii — Grayia spinosa alliance
- Ephedra viridis alliance
- 21′.
Stands with other species dominant to co-dominant
- 22.
Rabbit brush and other early seral species dominant in various settings including washes
- Encelia (actoni, virginensis) — Viguiera reticulata alliance
- Ericameria linearifolia — Cleome isomeris alliance
- Ericameria nauseosa alliance
- Ericameria paniculata alliance
- Ericameria parryi alliance
- Ericameria teretifolia alliance
- Eriogonum fasciculatum — Viguiera parishii alliance
- Gutierrezia sarothrae — Gutierrezia microcephala alliance
- Prunus fasciculata — Salazaria mexicana alliance
- 22′.
Other species dominant on bajadas and desert slopes
- Ambrosia salsola — Bebbia juncea alliance
- Amelanchier utahensis — Cercocarpus montanus — Cercocarpus intricatus alliance
- Amphipappus fremontii — Salvia funerea alliance
- Atriplex canescens alliance
- Atriplex confertifolia alliance
- Atriplex hymenelytra alliance
- Atriplex polycarpa alliance
- Cercocarpus ledifolius alliance
- Coleogyne ramosissima alliance
- Ephedra nevadensis — Lycium andersonii — Grayia spinosaalliance
- Eriogonum spp. — Poa secunda alliance
- Eriogonum wrightii — Eriogonum heermannii — Buddleja utahensis alliance
- Krascheninnikovia lanata alliance
- Menodora spinescens alliance
- Nolina (parryi, bigelovii) alliance
- Psorothamnus fremontii — Psorothamnus polydenius alliance
- Purshia stansburiana alliance
- Purshia tridentata — Artemisia tridentata alliance
- Quercus turbinella alliance
- 20′.
Stands of the warm deserts including the Colorado, Mojave, Sonoran deserts and the southern San Joaquin Valley and surrounding hills
- 23.
Shrubs conspicuous but herbs may be dominant; shrub cover >2%
- Atriplex hymenelytra alliance
- 23′.
Stands dominated by shrubs; herb cover may be high, especially in wet years
- 24.
Stands of riparian bottomlands, washes, alkaline sinks, saline wetlands, and disturbed areas including bajadas
- 25.
Stands of washes and other intermittent watercourses—wash woodland/scrub
- 26.
Stands with low- to medium-sized shrubs (1–3 m)
- Acacia spp. — Grevillea spp. — Leptospermum laevigatum alliance
- Agave deserti alliance
- Ambrosia salsola — Bebbia juncea alliance
- Baccharis emoryi — Baccharis sergiloides alliance
- Encelia (actoni, virginensis) — Viguiera reticulata alliance
- Ephedra californica — Ephedra trifurca alliance
- Ericameria paniculata alliance
- Fallugia paradoxa alliance
- Lepidospartum squamatum alliance
- Prunus fasciculata — Salazaria mexicana alliance
- Senegalia greggii — Hyptis emoryi — Justicia californica alliance
- Ziziphus obtusifolia special stands
- 26′.
Stands with both medium and tall shrubs (1.5–15 m)
- Castela emoryi special stands
- Celtis laevigata var. reticulata — Rhus trilobata provisional alliance*
- Chilopsis linearis — Psorothamnus spinosus alliance*
- Koeberlinia spinosa special stands
- Parkinsonia florida — Olneya tesota alliance*
- Pluchea sericea alliance
- Prosopis glandulosa — Prosopis velutina — Prosopis pubescens alliance*
- Rhus trilobata — Crataegus rivularis — Forestiera pubescens alliance
- Salix exigua alliance
- Salix boothii — Salix geyeriana — Salix lutea alliance
- Senegalia greggii — Hyptis emoryi — Justicia californica alliance
- Tamarix spp. semi-natural alliance
- 25′.
Stands of alkaline or saline basins or wetlands—alkali and saltbush scrubs
- Allenrolfea occidentalis alliance
- Arthrocnemum subterminalis alliance+
- Atriplex canescens alliance
- Atriplex hymenelytra alliance
- Atriplex lentiformis alliance
- Atriplex polycarpa alliance
- Atriplex spinifera alliance
- Distichlis spicata Interior alliance+
- Sarcobatus vermiculatus alliance
- Sarcocornia pacifica (Salicornia depressa) alliance+
- Suaeda moquinii alliance
- 24′.
Stands of uplands; shrubs and perennial grasses may be co-dominant—desert scrub
- 27.
Stands of alliances localized in the Colorado, Sonoran, and southeastern Mojave deserts—tall desert scrub/woodland and desert succulent scrub
- Bursera microphylla special stands*
- Cylindropuntia bigelovii alliance
- Carnegiea gigantea — Parkinsonia microphylla — Prosopis velutina alliance
- Eriogonum fasciculatum — Viguiera parishii alliance
- Koeberlinia spinosa special stands
- Prunus fremontii alliance
- Simmondsia chinensis provisional alliance
- Tetracoccus hallii provisional alliance
- Ziziphus obtusifolia special stands
- 27′.
Stands widespread across the warm deserts or localized in the Mojave Desert
- 28.
Stands with burro bush, brittle bush, and/or creosote bush dominant, widespread in the warm deserts
- Ambrosia dumosa alliance
- Encelia farinosa alliance
- Larrea tridentata alliance
- Larrea tridentata — Ambrosia dumosa alliance
- Larrea tridentata — Encelia farinosa alliance
- Pleuraphis rigida alliance+
- 28′.
Stands with other species dominant, especially in the Mojave Desert
- Ambrosia salsola — Bebbia juncea alliance
- Amphipappus fremontii — Salvia funerea alliance
- Artemisia tridentata alliance
- Atriplex canescens alliance
- Atriplex hymenelytra alliance
- Atriplex polycarpa alliance
- Coleogyne ramosissima alliance
- Cylindropuntia acanthocarpa / Pleuraphis rigida provisional alliance
- Ephedra californica — Ephedra trifurca alliance
- Ephedra funerea alliance
- Ephedra nevadensis — Lycium andersonii — Grayia spinosa alliance
- Menodora spinescens alliance
- Mortonia utahensis alliance
- Psorothamnus fremontii — Psorothamnus polydenius alliance
- Quercus turbinella alliance
- Prunus fasciculata — Salazaria mexicana alliance
- Yucca brevifolia alliance*
- Yucca schidigera alliance
- *Treated in the tree alliance description
- +Treated in the herbaceous alliance description
