Carex congdonii Provisional Herbaceous Alliance
Congdon’s sedge talus
Congdon’s sedge talus
Summary Information
- Primary Life FormHerb
- Elevation2600-3700 m
- State RarityS2
- Global RarityG2
- DistributionUSA: CA (NRCS) (Calflora), NV?
- Endemic to CaliforniaNo
- Endemic to California Floristic Province and DesertsYes
- Date Added2009/09/01
Characteristic Species
Carex congdonii is characteristically present in the herbaceous layer with Arnica amplexicaulis. Emergent shrubs may be present at low cover, including Sambucus racemosa.
Vegetation Layers
Herbs < 90 cm; cover is open.
Habitats
Talus and outcrops. Soils are rocky or sandy.
Other Habitat, Alliance, and Community Groupings
MCV (1995) | Alpine habitat |
NVCS (2009) | Not treated |
Calveg | Perennial grasses and forbs |
Holland | Sierra Nevada fell-field, Dry alpine talus and scree slope |
Munz | Alpine fell-fields |
WHR | Alpine dwarf-shrub |
CDFW CA Code | 45.160.00 |
Remarks
Carex congdonii is a caespitose sedge with short rhizomes. Basal leaf sheaths are purple, and the blades hairy. Flower spikes are 3 to 20 with the lower ones pistillate and ascending, the terminal ones staminate and erect (Ball and Reznicek 2002).
Plants are typical of alpine talus, often on south-facing or neutral exposures (not shady northerly exposures) where they form small clones, usually in association with subterranean moisture. The species occupies relatively dry sites compared to other clonal alpine sedges (e.g., C. breweri, C. spectabilis). The culms are coarser and taller than those of other clonal alpine sedges. Probably the most important disturbance processes are rockslides and variable moisture availability due to fluctuating precipitation patterns over the years.
Plants are typical of alpine talus, often on south-facing or neutral exposures (not shady northerly exposures) where they form small clones, usually in association with subterranean moisture. The species occupies relatively dry sites compared to other clonal alpine sedges (e.g., C. breweri, C. spectabilis). The culms are coarser and taller than those of other clonal alpine sedges. Probably the most important disturbance processes are rockslides and variable moisture availability due to fluctuating precipitation patterns over the years.
Observations
Carex congdonii (a CNPS list 4.3 plant ) is endemic to the Sierra Nevada (M261Eo). Taylor (1984, see Cheng 2004) described two associations from a few samples at Harvey Monroe Hall RNA, one associated with Arnica amplexicaulis, and the other with Sambucus racemosa. Other stands observed but not sampled were those on the west side of Mount Dana, the west side of Virginia Pass, and the southwest side of Merced Peak (Keeler-Wolf et al. 2003b). We need additional sampling and analysis to understand the role of C. congdonii in the alpine vegetation of the Sierra Nevada.
References
- [1] Taylor, D.W. 1984
- Cheng, S. 2004
- Sawyer, J.O.;Keeler-Wolf, T. 2007