Carex (aquatilis, lenticularis) Herbaceous Alliance
Water sedge and lakeshore sedge meadows
Water sedge and lakeshore sedge meadows
USDA Ecological Section Map
Summary Information
- Primary Life FormHerb
- Elevation1200-3400 m
- State RarityS3
- Global RarityG5
- DistributionCAN: AB, MB, NB, ON, QC. USA: AZ, CA, CO, ID, MI, MN, MT, ND, NM, NV, OR, SD, UT, WA, WY (NatureServe)
- Endemic to CaliforniaNo
- Endemic to California Floristic Province and DesertsNo
- Date Added2009/09/01
Characteristic Species
Carex aquatilis and/or Carex lenticularis is dominant or co-dominant in the herbaceous layer with Achillea millefolium, Bistorta bistortoides, Carex jonesii, Carex luzulina, Carex microptera, Carex simulata, Carex utriculata, Deschampsia cespitosa, Dodecatheon jeffreyi, Eleocharis quinqueflora, Epilobium ciliatum, Hypericum anagalloides, Juncus arcticus, Mimulus primuloides, Muhlenbergia filiformis, Oreostemma alpigenum, Perideridia parishii, Phleum alpinum, Phleum pratense, Poa pratensis, Poa secunda, Rumex crispus, Scirpus congdonii, Taraxacum officinale and Viola macloskeyi. Emergent trees and shrubs may be present at low cover: such as Pinus contorta ssp. murrayana Cornus sericea, Kalmia microphylla, Salix spp. and Vaccinium uliginosum. Mosses may be abundant, including Aulacomnium palustre and Campylium stellatum
Vegetation Layers
Emergent trees, if present, are sparse. Herbs < 1.5 m; cover is open to continuous.
Membership Rules
- Carex aquatilis or C. lenticularis is ≥ 30% relative cover in the herbaceous layer; C. scopulorum, C. utriculata, or C. vesicaria absent or at relatively low cover (Potter 2005).
- Carex aquatilis and/or C. lenticularis has ≥ 30% relative cover in the herbaceous layer; no other Carex spp. has greater cover (Boul et al. 2021b).
Habitats
Wet meadows in basins, shallow lakes and margins, floodplains; montane fens; and along streams in narrow riparian ecotones. Soils have high organic material content; some are sandy. The USACE Wetland Inventory (2018 national list) recognizes Carex aquatilis and C. lenticularis as OBL plants.
Other Habitat, Alliance and Community Groupings
| MCV (1995) | Sedge series |
| NVCS (2009) | Carex aquatilis seasonally flooded herbaceous alliance |
| Calveg | Wet grasses and forbs, Tule-Cattail |
| Holland | Wet montane meadow, Wet subalpine or alpine meadow, Freshwater seep, Fen |
| Munz | Freshwater marsh |
| WHR | Wet meadow |
| CDFW CA Code | 45.168.00 |
National Vegetation Classification Hierarchy
| Formation Class | Mesomorphic Shrub and Herb Vegetation (Shrubland and Grassland) |
| Formation Subclass | Temperate and Boreal Shrubland and Grassland |
| Formation | Temperate and Boreal Freshwater Marsh |
| Division | Western North American Freshwater Marsh |
| Macro Group | Western North America Wet Meadow and Low Shrub Carr |
| Group | Western Cordilleran montane-boreal summer-saturated meadow |
Remarks
Carex aquatilis is a 150-cm tall, rhizomatous sedge that forms dense clumps. It has a circumboreal range, and plants have an extensive root system that can tolerate anoxic conditions (Hauser 2006a). Two of the four varieties (var. aquatilis and var. dives) grow in California.
Carex lenticularis is a 90-cm tall, caespitose sedge without rhizomes that forms dense clumps. Three of the five varieties (var. impressa, var. limnophila, and var. lipocarpa) grow in California. C. lenticularis is difficult to distinguish from C. aquatilis in the field (Potter 2005).
In general, stands of this alliance are dominated by wet meadow sedges and spike rushes that dominate the herbaceous layer. Both Carex aquatilis and C. lenticularis grow in seasonally or permanently saturated meadows along lakes and streams interspersed with forest edges.
Potter (2005) included both sedges in a single association in his treatment for the Sierra Nevada meadows. Similarly, Pierce and Johnson (1986) identified C. lenticularis as dominant or codominant in a meadow type in a wetland classification for west-central Montana. Christy (2004) placed stands dominated by the different varieties in separate associations in a Carex aquatilis alliance and stands of C. lenticularis in a separate alliance in a northwestern Oregon study. The principal difference appeared to be more woody plants, such as Rhododendron columbianum and Vaccinium uliginosum, in C. aquatilis stands than in those of C. lenticularis. The latter alliance tended to have higher cover of large herbs such as Bistorta bistortoides and Senecio triangularis. At present, we consider these differences to be at the association level of this alliance. Hauser (2006a) also stated that C. aquatilis is co-dominant with C. rostrata in many states of the West.
However, further analysis and review of wet meadow and fen alliances is needed to determine if separate and/or broader alliance designations are warranted, as has been done by the NVC.
Carex lenticularis is a 90-cm tall, caespitose sedge without rhizomes that forms dense clumps. Three of the five varieties (var. impressa, var. limnophila, and var. lipocarpa) grow in California. C. lenticularis is difficult to distinguish from C. aquatilis in the field (Potter 2005).
In general, stands of this alliance are dominated by wet meadow sedges and spike rushes that dominate the herbaceous layer. Both Carex aquatilis and C. lenticularis grow in seasonally or permanently saturated meadows along lakes and streams interspersed with forest edges.
Potter (2005) included both sedges in a single association in his treatment for the Sierra Nevada meadows. Similarly, Pierce and Johnson (1986) identified C. lenticularis as dominant or codominant in a meadow type in a wetland classification for west-central Montana. Christy (2004) placed stands dominated by the different varieties in separate associations in a Carex aquatilis alliance and stands of C. lenticularis in a separate alliance in a northwestern Oregon study. The principal difference appeared to be more woody plants, such as Rhododendron columbianum and Vaccinium uliginosum, in C. aquatilis stands than in those of C. lenticularis. The latter alliance tended to have higher cover of large herbs such as Bistorta bistortoides and Senecio triangularis. At present, we consider these differences to be at the association level of this alliance. Hauser (2006a) also stated that C. aquatilis is co-dominant with C. rostrata in many states of the West.
However, further analysis and review of wet meadow and fen alliances is needed to determine if separate and/or broader alliance designations are warranted, as has been done by the NVC.
Life History Traits of the Principal Species
| Carex aquatilis | Carex lenticularis | |
|---|---|---|
| Life forms | Polycarpic perennial; herb; rhizomatous | Polycarpic perennial; herb; rhizomatous |
| Seed storage | Transient | Transient |
| Seed longevity | Short | Short |
| Mode of dispersal | Animal; gravity; water/hydrological | Animal; gravity; water/hydrological |
| Germination agents | Stratification—winter | Stratification—winter |
| Mode of sprouting | Underground structures | Underground structures |
| Survivability after fire/disturbance | Fire-hardy; high sprouter | Fire-hardy; high sprouter |
| Disturbance-stimulated flowering | No | No |
| Reproductive range | Long-lived | Long-lived |
| Recruitment | Low; episodic | Low; episodic |
| Regional variation | High | High |
Fire Characteristics
Fluvial processes rather than fire primarily disturb the alliance. Carex aquatilis recovers rapidly when rhizome buds sprout; C. lenticularis is not capable of sprouting.
| Fire return interval | — |
| Seasonality | — |
| Size/extent | — |
| Complexity | — |
| Intensity | — |
| Severity | — |
| Type | — |
| Regional knowledge | — |
Regional Status
The range of Carex aquatilis and C. lenticularis includes the Central California Coast (261A), Klamath Mountains (M261Ag, At), Modoc Plateau (M261G), and Northern California Coast (263A).
- Klamath Mountains (M261Ad, Ag, Ai-j, An, Aq, At). Stands are presumed present based on CCH and calflora records.
- Modoc Plateau (M261Gb, Gf, Gh-i, Gm). Stands are scattered throughout the section along stream channels and at the edges of meadows (Boul et al. 2020).
- Mono (341Dl). Stands of C. aquatilis occur in wet meadows and riparian zones at the Glass Mountain area with C. nebrascensis and willows such as Salix exigua, S. geyeriana, and S. lutea (Honer 2001).
- Northern California Coast (263Aa, Ad-e, Ag). Stands are presumed present based on CCH and calflora records.
- Northern California Coast Ranges (M261Ba). Small stands of C. aquatilis occur in fens at the higher elevations of the Yolla Bolly Mountains within the Abies magnifica zone at more than 1900 m (Keeler-Wolf and Keeler-Wolf 1974).
- Northwestern Basin and Range (342Bd). Stands are present in Balls Canyon at the northwestern base of Shaffer Mountain, in some small patches along Willow Creek, and in a meadow on Painters Creek in the north of the subsection (Boul et al. 2020).
- Sierra Nevada (M261Ea-h, Ej-r, Eu). Stands occur generally north of the Kings River (Potter 2005), sporadically in Yosemite National Park (Keeler-Wolf et al. 2003b), and as far north as Bucks Lake Wilderness, including Mount Pleasant RNA (Cheng 2004). According to Potter (2005), common adjacent stands include those of the Carex nebrascensis, Carex (utriculata, vesicaria), Eleocharis quinqueflora, Oxypolis occidentalis, and Scirpus microcarpus alliances on wet sites; Poa pratensis and Veratrum californicum alliances on moist sites; and Cistanthe (umbellata)-Gayophytum (diffusum) alliance on dry sites. Associated shrub stands are those of the Salix eastwoodiae, Salix lemmonii, and Vaccinium cespitosum alliances. Common adjacent forest stands are those of the moist meadow edge associations of the Pinus contorta ssp. murrayana alliance.
- Southern California Mountains and Valleys (M262Bh). No description available
- Southern Cascades (M261Dd, Df-g, Di-j, Dm). Stands of C. aquatilis are common in the section in higher mountain meadows (S. Smith 1998b).
Management Considerations
Sedges are moderately palatable to livestock. Carex aquatilis is particularly susceptible to grazing and trampling (Hauser 2006a, Potter 2005, S. Smith 1998b). Erosion and stream downcutting, often the result of cumulative impacts of grazing and timber harvest, has eliminated and reduced stands by dropping water tables. Managers should limit these impacts in and adjacent to stands. C. aquatilis is excellent for stabilizing stream banks and filtering sediments with its sod-forming, strongly rhizomatous growth (Hauser 2006a).
Associations
- Carex aquatilis [2], [4]
- Carex aquatilis - Carex lenticularis [3], [5]
- Carex lenticularis / Aulacomnium palustre [1]
- Carex lenticularis / Perideridia parishii [1]
References
- [1] Cooper, D.J.;Wolf, E.C. 2006
- [2] Keeler-Wolf, T.;Schindel, M.;San, S.;Moore, P.;Hickson, D. 2003b
- [3] Potter, D.A. 2005
- [4] Smith, S. 1998b
- [5] Boul, R.;Keeler-Wolf, T.;Ratchford, J.;Haynes, T.;Hickson, D.;Yacoub, R.;Harbert, B.;Evens, J. 2021b
- Christy, J.A. 2004
- Hauser, A.S. 2006a