USDA Ecological Section Map
Primary Life FormHerb
DistributionUSA: CA, OR (TJM2)
Endemic to CaliforniaNo
Endemic to California Floristic Province and DesertsNo
Carex barbarae is dominant or co-dominant in the herbaceous layer with Asclepias fascicularis, Carex praegracilis, Eleocharis spp., Epilobium ciliatum, Euthamia occidentalis, Juncus spp., Perideridia kelloggii, Senecio minimus, Solidago spp. and Urtica dioica. Emergent trees and shrubs may be present at low cover, including trees Fraxinus latifolia, Platanus racemosa, Quercus agrifolia or Quercus lobata and shrubs:Cephalanthus occidentalis and Rubus spp.
Herbs < 1 m; cover is intermittent to continuous.
- Carex barbarae > 50% relative cover in the herbaceous layer (Evens and Kentner 2006, Hickson and Keeler-Wolf 2007, Klein et al. 2007, Buck-Diaz et al. 2021).
- Carex barbarae > 50% relative cover in seasonally or intermittently saturated wetlands (Buck-Diaz et al. 2021).
Stream beds, river terraces, levees. Soils are silts to sands and are seasonally or intermittently saturated. The USACE Wetland Inventory (2018 national list) recognizes Carex barbarae as FAC.
||Wet grasses and forbs
||Great Valley valley oak riparian forest
|CDFW CA Code
||Mesomorphic Shrub and Herb Vegetation (Shrubland and Grassland)
||Temperate and Boreal Shrubland and Grassland
||Temperate and Boreal Freshwater Marsh
||Western North American Freshwater Marsh
||Western North America Wet Meadow and Low Shrub Carr
||Californian warm temperate marsh/seep
Carex barbarae grows in cismontane California and southern Oregon in seasonally wet riparian sites. Its leathery leaves are not usually tufted, and they have shredding leaf sheath fronts. Its inflorescences are large and pendent (often 3-8 cm long) with well-developed pistillate spikelets and usually staminate tips.
Carex barbarae is tolerant of shade and occurs in winter-deciduous gallery woodlands (Holland 1986). In the Central Valley and central Coast Ranges, it occurs regularly as an understory in Quercus lobata stands but does form stands without tree canopies. In some areas, it may be replaced by aggressive non-native woody species, such as Rubus armeniacus though in other areas native species such as R. ursinus may be present. In similar soil-moisture settings, it can occur away from trees, where perhaps they have been cleared or where more frequently flooding occurs, fostering patches of this alliance.
||Polycarpic perennial; herb; rhizomatous
|Mode of dispersal
||Animal; gravity; water/hydrological
|Mode of sprouting
||Buds on large branches or trunks (culms, tillers)
|Survivability after fire/disturbance
||Fire-hardy; high sprouter
||Life of plant
Fluvial processes and mechanical clearing rather than fire primarily disturb stands. However, stands may be fostered by frequent surface fires.
|Fire return interval
||Short to medium
||Up to stand size
The range of Carex barbarae includes low elevations of the Klamath Mountains (M261A), Northern California Coast Ranges (M261B), Northern California Interior Coast Ranges (M261C), Southern California Coast (261B), and Southern California Mountains and Valleys (M261B).
- Central California Coast Ranges (M262Ac, Af). Patches associated with Quercus lobata woodlands are scattered in the section.
- Great Valley (262Ac, Af, Ai, Al-m, Aq-r). Hickson and Keeler-Wolf (2007) sampled a stand in the Sacramento-San Joaquin River delta in San Joaquin Co. Large colonies of C. barbarae occur occasionally in association with riparian forests of the Kaweah River in Tulare Co. (Urtecho et al. 2002).
- Northern California Coast (263Aj, Al). Stands at Mount Tamalpais (Evens and Kentner 2006) and elsewhere in Marin Co. exist in active creek channels. In Sonoma Co., the alliance has been documented at Laguna de Santa Rosa (Klein et al. 2015).
- Sierra Nevada Foothills (M261Fa-b). Klein et al. (2007) sampled stands in the northern subsections in El Dorado and Placer Cos. Small stands are also associated with riparian woodlands along Big Chico Creek. Stands appear to occur at least as far south as the Kings River.
Carex barbarae, commonly called white-root, has white, long, fibrous rhizomes used in basketry. It has cultural significance for Native Americans of the Central Valley and the Coast Ranges with recorded historic use by 22 tribes (Stevens 2004). These tribes maintained large beds of C. barbarae (Stevens 1999, 2003). C. barbarae is difficult for basket weavers to obtain currently because of the elimination of traditional gathering sites, especially with the destruction of most valley oak woodlands and the difficulty of access to existing stands (Stevens 2000c).
Carex barbarae is useful in riparian restoration, stream bank stabilization, and erosion control. Plants readily establish under a wide variety of environmental conditions, and mature plants have well-developed, deep root systems that are resilient to low-intensity fire (Stevens 2000c). However, stands have been impacted by agricultural and urban expansion, hydrologic modification, and cessation of traditional management practices.
- Carex barbarae , , , , 
-  Evens, J.M.;Kentner, E. 2006
-  Klein, A.;Crawford, J.;Evens, J.;Keeler-Wolf, T.;Hickson, D. 2007
-  Buck-Diaz, J.;Batiuk, S.;Evens, J.M. 2012
-  Klein, A.;Keeler-Wolf, T.;Evens, J. 2015
-  Buck-Diaz, J.;Sikes, K.;Evens, J.M. 2021
- Hickson, D.;Keeler-Wolf, T. 2007
- Holland, R.F. 1986
- Stevens, M. 2000c
- Stevens, M.L. 1999
- Stevens, M.L. 2003
- Stevens, M.L. 2004
- Urtecho, R.;Bravin, R.;Anaya, M.;Benoy, C. 2002