Sparganium (angustifolium) Herbaceous Alliance
Mats of bur-reed leaves
Mats of bur-reed leaves
USDA Ecological Section Map
Summary Information
- Primary Life FormHerb
- Elevation0-3700 m
- State RarityS3?
- Global RarityG4
- DistributionCAN: BC?. USA: CA, CO, ID, OR, WA, WY (NatureServe)
- Endemic to CaliforniaNo
- Endemic to California Floristic Province and DesertsNo
- Date Added1995/11/01
Characteristic Species
Sparganium angustifolium or another Sparganium species is dominant on the water surface with Brasenia schreberi, Callitriche spp., Carex utriculata, Carex vesicaria, Nuphar lutea, Potamogeton spp., Stuckenia spp., Typha spp. and Utricularia macrorhiza.
Vegetation Layers
Herbs <1 m; cover is open to continuous.
Membership Rules
- Sparganium angustifolium > 50% relative cover on the water surface (Keeler-Wolf et al. 2003b).
- Sparganium eurycarpum is > 50% relative cover in wetlands with other forbs including Agrostis pallens, Oenanthe sarmentosa, and Rumex conglomeratus (Buck-Diaz et al. 2021, Sikes et al. 2021, Sikes et al. 2023).
- Sparganium eurycarpum is > 50% relative cover in wetlands with other forbs including Lemna (Sikes et al. 2025).
Habitats
Ponds with shallow water or near the shoreline of deeper ponds or lakes with gravelly or muddy bottoms. The USFWS Wetland Inventory (1996 national list) recognizes Sparganium angustifolium as an OBL plant.
Other Habitat, Alliance and Community Groupings
| MCV (1995) | Bur-reed series |
| NVCS (2009) | Sparganium angustifolium permanently flooded herbaceous alliance |
| Calveg | Tule-Cattail, Water |
| Holland | Montane freshwater marsh |
| Munz | Freshwater marsh |
| WHR | Fresh emergent wetland |
| CDFW CA Code | 52.010.00 |
National Vegetation Classification Hierarchy
| Formation Class | Hydromorphic Vegetation (Aquatic Vegetation) |
| Formation Subclass | Freshwater Aquatic Vegetation |
| Formation | Freshwater Aquatic Vegetation |
| Division | North American Freshwater Aquatic Vegetation |
| Macro Group | Western North American Freshwater Aquatic Vegetation |
| Group | Temperate Pacific freshwater aquatic bed |
Remarks
Sparganium angustifolium is a floating-leaved, anchored hydrophyte. Its leaves are narrow, flat blades. The flowers are crowded along the central stem, forming spheric heads of independent female or male inflorescences. As with most aquatic plants, the seeds may lose viability if they dry out (Anderson 2003b). However, seeds may remain viable for more than 4 years, such as in S. erectum, and they germinate erratically and throughout the year (Cook 1962).
Sparganium angustifolium is a relatively invariable species that forms fertile hybrids with S. emersum. Flat to convex leaves and contiguous staminate heads distinguish S. angustifolium. Leaves that are triangular, at least at the base, and numerous staminate heads, at least some of which are not contiguous, distinguish S. emersum. S. eurycarpum grows along the coast and inland in California, but not in salt marshes. S. natans grows in cool, quiet, slightly acidic to somewhat basic waters of bays, pools, ditches, and fens (Kaul 2000). The vegetational relationships among the bur-reeds need clarification.
Sparganium angustifolium is common in California’s mountain lakes, regularly forming stands in the middle of small ponds and near lake shorelines. The habitat setting is similar to that of Nuphar lutea, but S. angustifolium typically occupies shallower water that may fluctuate more widely during the growing season.
Sparganium angustifolium is a relatively invariable species that forms fertile hybrids with S. emersum. Flat to convex leaves and contiguous staminate heads distinguish S. angustifolium. Leaves that are triangular, at least at the base, and numerous staminate heads, at least some of which are not contiguous, distinguish S. emersum. S. eurycarpum grows along the coast and inland in California, but not in salt marshes. S. natans grows in cool, quiet, slightly acidic to somewhat basic waters of bays, pools, ditches, and fens (Kaul 2000). The vegetational relationships among the bur-reeds need clarification.
Sparganium angustifolium is common in California’s mountain lakes, regularly forming stands in the middle of small ponds and near lake shorelines. The habitat setting is similar to that of Nuphar lutea, but S. angustifolium typically occupies shallower water that may fluctuate more widely during the growing season.
Life History Traits of the Principal Species
| Sparganium angustifolium | |
|---|---|
| Life forms | Polycarpic perennial; herb |
| Seed storage | Soil |
| Seed longevity | Long |
| Mode of dispersal | Animal; water/hydrological |
| Germination agents | Unknown |
| Mode of sprouting | Underground structures (rhizomes) |
| Survivability after fire/disturbance | Fire-hardy; no/low sprouter to high sprouter |
| Disturbance-stimulated flowering | No |
| Reproductive range | Life of plant |
| Recruitment | Episodic |
| Regional variation | Low |
Fire Characteristics
Processes other than fire disturb stands of the alliance. Disturbance comes largely from seasonal water level fluctuation and freezing.
| Fire return interval | — |
| Seasonality | — |
| Size/extent | — |
| Complexity | — |
| Intensity | — |
| Severity | — |
| Type | — |
| Regional knowledge | — |
Regional Status
The range of Sparganium species includes the Central California Coast (261A), Central California Coast Ranges (M262A), Modoc Plateau (M261G), Northern California Coast Ranges (M261B), Sierra Nevada Foothills (M261F), Southern California Coast (261B), and Southern California Mountains and Valleys (M262B).
- Central California Coast (261Af). One stand of Sparganium eurycarpum was sampled in a wetland near the coast in San Mateo Co. (Sikes et al. 2021).
- Great Valley (262Al). Stands of Sparganium eurycarpum occur in the Sacramento-San Joaquin River delta (Hickson and Keeler-Wolf 2007).
- Klamath Mountains (M261Ad, Ag, Aj, Ap, At). Mats of S. angustifolium occupy lakes and ponds at montane elevations.
- Northern California Coast (263Ak-l). Stands of S. eurycarpum occur at Point Reyes National Seashore and other locations in the section (Buck-Diaz et al. 2021).
- Sierra Nevada (M261Ee, Eh, Ej-m, Eo, Eq-r, Et-u). Mats of S. angustifolium occur in lakes and ponds at montane elevations in Yosemite National Park and environs (Keeler-Wolf et al. 2003b). Stands of S. eurycarpum also exist in this section.
- Southern Cascades (M261Df, Dm). Mats of S. angustifolium exist in lakes and ponds at montane elevations.
Management Considerations
Sparganium species are excellent food and habitat for waterfowl. The tubers are edible and have herbal properties (Anderson 2003b).
Associations
- Sparganium angustifolium [1]
- Sparganium eurycarpum [2], [3], [4], [5]
References
- [1] Keeler-Wolf, T.;Schindel, M.;San, S.;Moore, P.;Hickson, D. 2003b
- [2] Buck-Diaz, J.;Sikes, K.;Evens, J.M. 2021a
- [3] Sikes, K.;Buck-Diaz, J.;Evens, J. 2021
- [4] Sikes, K.;Buck-Diaz, J.;Vu, S.;Evens, J. 2023
- [5] Sikes, K.;Buck-Diaz, J.;Vu, S.;Bibbo, M.;Evens, J. 2025
- Anderson, M.K. 2003b
- Barry, W.J. 1989a
- Barry, W.J. 1989b
- Cheatham, N.H.;Haller, J.R. 1975
- Mason, H.L. 1957