Carex nigricans Provisional Herbaceous Alliance
Black alpine sedge meadows
Black alpine sedge meadows
Summary Information
- Primary Life FormHerb
- Elevation3000-3700 m
- State RarityS3?
- Global RarityG4
- DistributionCAN: AB, BC. USA: CA, CO, ID, MT, OR, WA, WY (NatureServe)
- Endemic to CaliforniaNo
- Endemic to California Floristic Province and DesertsNo
- Date Added2009/09/01
Characteristic Species
Carex nigricans is dominant or co-dominant in the herbaceous layer with Caltha leptosepala, Carex aquatilis, Carex canescens, Carex pellita, Danthonia intermedia, Deschampsia cespitosa, Dodecatheon spp., Epilobium spp., Gentiana spp., Pedicularis attollens, Pedicularis groenlandica, Phleum alpinum and Symphyotrichum spathulatum. Shrubs may be present at low cover, including Kalmia microphylla, Phyllodoce breweri, Rhododendron columbianum, Salix petrophila or Vaccinium cespitosum.
Vegetation Layers
Herbs < 50 cm; cover is continuous.
Habitats
Low-gradient basin floors and lakeshores associated with late-melting snowfields; in seeps along slopes. Soils are high in organic material and may be hummocky with water tables near the surface. The USFWS Wetland Inventory (1996 national list) recognizes Carex nigricans as a FACW plant.
Other Habitat, Alliance, and Community Groupings
MCV (1995) | Sedge series, Subalpine meadow habitat |
NVCS (2009) | Carex nigricans seasonally flooded herbaceous alliance |
Calveg | Perennial grasses and forbs |
Holland | Wet subalpine or alpine meadow, Alpine snowbank margin |
Munz | Alpine fell-fields |
WHR | Alpine dwarf-shrub, Wet meadow |
CDFW CA Code | 45.164.00 |
Remarks
Carex nigricans is a loosely caespitose sedge with creeping rhizomes. Leaves are flat and channeled. The solitary flower spike is androgynous, rarely entirely staminate, or rarely entirely pistillate and terminal (Hurd et al. 1998).
The alliance exists in the mountains of the Pacific Northwest where C. nigricans mixes with Deschampsia atropurpurea and Luetkea pectinata, and in Rocky Mountains with Phleum alpinum (NatureServe 2007a). Studies in Washington’s Olympic Mountains suggest that C. nigricans stands are particularly sensitive to shifts in winter snowpack accumulation and a bellwether for climate change (Gavin and Brubaker 1999).
The alliance exists in the mountains of the Pacific Northwest where C. nigricans mixes with Deschampsia atropurpurea and Luetkea pectinata, and in Rocky Mountains with Phleum alpinum (NatureServe 2007a). Studies in Washington’s Olympic Mountains suggest that C. nigricans stands are particularly sensitive to shifts in winter snowpack accumulation and a bellwether for climate change (Gavin and Brubaker 1999).
Observations
The range of Carex nigricans in California includes the Klamath Mountains (M261A), Sierra Nevada (M261Eo), and Southern Cascades (M261B). The alliance has been sampled in California in Harvey Monroe Hall RNA (Taylor 1984, see Cheng 2004) and in Yosemite National Park (Keeler-Wolf et al. 2003b, see also Sawyer and Keeler-Wolf 2007). Both studies recognized a Carex nigricans-Kalmia microphylla association based on limited data sets. Stands in California may not represent the Carex nigricans alliance as well as those defined outside the state. We need further sampling and analysis to understand fully this alliance’s relationship with the other closely related Calamagrostis muiriana, Kalmia microphylla, and Salix petrophila alliances.
References
- [1] Taylor, D.W. 1984
- Christy, J.A. 2004
- Sawyer, J.O.;Keeler-Wolf, T. 2007