Print Report
A4170 Centromadia pungens - Hemizonia sp. Vernal Pool Alliance
Type Concept Sentence: Centromadia pungens and/or a Hemizonia species is conspicuous to dominant in the herbaceous layer. This alliance is found in vernally wet habitats, including edges of alkaline vernal pools, bottoms of shallow pools, and alkaline flats subjected to periodic or intermittent water inundation at elevations ranging from 0-900 m in central California.
Common (Translated Scientific) Name: Common Tarweed - Tarweed species Vernal Pool Alliance
Colloquial Name: Tarweed Alkali Vernal Pool & Flat
Hierarchy Level: Alliance
Type Concept: This alliance consists of intermittent cover of herbs <1 m in height. Centromadia pungens and/or a Hemizonia species is conspicuous to dominant in the herbaceous layer with Atriplex spp., Bromus spp., Deschampsia danthonioides, Downingia bella, Erodium cicutarium, Frankenia salina, Hirschfeldia incana, Hordeum murinum, Lasthenia californica, Lasthenia fremontii, Trifolium depauperatum, and Trifolium variegatum. Emergent shrubs may be present at low cover, including Suaeda moquinii. This alliance is found in vernally wet habitats, including edges of alkaline vernal pools, bottoms of shallow pools, and alkaline flats subjected to periodic or intermittent water inundation at elevations ranging from 0-900 m in central California. Soils are fine-textured alluvium, sometimes underlain by claypan or another impervious layer.
Diagnostic Characteristics: Centromadia pungens >30% relative cover in the herbaceous layer (Klein and Evens 2006); or Centromadia pungens, Deschampsia danthonioides, Trifolium spp., Phalaris lemmonii, Medicago polymorpha, and Downingia bella present in the herbaceous layer (Barbour et al. 2007b).
Rationale for Nominal Species or Physiognomic Features: No Data Available
Classification Comments: Centromadia pungens is indicative of fine-textured clay soils, which are usually associated with seasonal saturation or flooding and alkalinity. These conditions typically occur in alkali vernal pools or swales, but may also occur on broad flats underlain by fine alkaline soils. Barbour et al. (2007b) defined stands of Centromadia pungens in a recent regional treatment of vernal pools as part of the Lasthenia fremontii - Distichlis spicata (Frankenia salina) alliance, restricted to alkaline or saline pools in the southern Sierra Nevada foothills. However, Centromadia pungens stands on vernal flats of southern California (Klein and Evens 2006), stands in vernal pools of the southern foothills, and stands in high marshes of the San Francisco Bay (Baye et al. 2000) can lack the strong presence of Distichlis spicata and Frankenia salina. This alliance (A4170) is considered appropriately distinct from the other vernal pool and salt marsh alliances.
Another tarweed, Hemizonia fitchii, occurs commonly throughout cismontane California. Barbour et al. (2007b) considered it a moderately present vernal pool plant indicator of the Downingia bicornuta - Lasthenia fremontii order, but not a strong indicator at the alliance or association levels. Hemizonia fitchii also occurs regularly in grasslands with clay soils, including serpentine areas.
Another tarweed, Hemizonia fitchii, occurs commonly throughout cismontane California. Barbour et al. (2007b) considered it a moderately present vernal pool plant indicator of the Downingia bicornuta - Lasthenia fremontii order, but not a strong indicator at the alliance or association levels. Hemizonia fitchii also occurs regularly in grasslands with clay soils, including serpentine areas.
Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available
Floristics: This alliance consists of intermittent cover of herbs <1 m in height. Centromadia pungens (= Hemizonia pungens) and/or a Hemizonia species is conspicuous to dominant in the herbaceous layer with Atriplex spp., Bromus spp., Deschampsia danthonioides, Downingia bella, Erodium cicutarium, Frankenia salina, Hirschfeldia incana, Hordeum murinum, Lasthenia californica, Lasthenia fremontii, Trifolium depauperatum, and Trifolium variegatum. Emergent shrubs may be present at low cover, including Suaeda moquinii.
Dynamics: No Data Available
Environmental Description: This alliance is found in vernally wet habitats, including edges of alkaline vernal pools, bottoms of shallow pools, and alkaline flats subjected to periodic or intermittent water inundation at elevations ranging from 0-900 m in central California. Soils are fine-textured alluvium, sometimes underlain by claypan or another impervious layer.
Geographic Range: This alliance occurs in California in the central coast, Great Central Valley, Sierra Nevada foothills and southern mountains and valleys.
Nations: US
States/Provinces: CA
Plot Analysis Summary:
http://vegbank.org/natureserve/ELEMENT_GLOBAL.2.943205
Confidence Level: Low - Poorly Documented
Confidence Level Comments: No Data Available
Grank: G2?
Greasons: No Data Available
| Type | Name | Database Code | Classification Code |
|---|---|---|---|
| Class | 2 Shrub & Herb Vegetation Class | C02 | 2 |
| Subclass | 2.C Shrub & Herb Wetland Subclass | S44 | 2.C |
| Formation | 2.C.4 Temperate to Polar Freshwater Marsh, Wet Meadow & Shrubland Formation | F013 | 2.C.4 |
| Division | 2.C.4.Nb Western North American Temperate Freshwater Marsh, Wet Meadow & Shrubland Division | D031 | 2.C.4.Nb |
| Macrogroup | 2.C.4.Nb.3 Winged Water-starwort - Elegant Calicoflower - California Eryngo Western North American Vernal Pool Macrogroup | M074 | 2.C.4.Nb.3 |
| Group | 2.C.4.Nb.3.a Californian Vernal Pool Group | G530 | 2.C.4.Nb.3.a |
| Alliance | A4170 Common Tarweed - Tarweed species Vernal Pool Alliance | A4170 | 2.C.4.Nb.3.a |
Concept Lineage: No Data Available
Predecessors: No Data Available
Obsolete Names: No Data Available
Obsolete Parents: No Data Available
Synonomy: = Centromadia (pungens) (Tar plant fields) Alliance (Sawyer et al. 2009) [44.160.00]
>< Northern Claypan Vernal Pool (#44120) (Holland 1986b)
>< Northern claypan vernal pool habitat (Sawyer and Keeler-Wolf 1995)
>< San Diego Mesa Claypan Vernal Pool (#44320) (Holland 1986b)
>< San Jacinto Valley vernal pool habitat (Sawyer and Keeler-Wolf 1995)
>< Wildflower Field (#42300) (Holland 1986b)
>< Northern Claypan Vernal Pool (#44120) (Holland 1986b)
>< Northern claypan vernal pool habitat (Sawyer and Keeler-Wolf 1995)
>< San Diego Mesa Claypan Vernal Pool (#44320) (Holland 1986b)
>< San Jacinto Valley vernal pool habitat (Sawyer and Keeler-Wolf 1995)
>< Wildflower Field (#42300) (Holland 1986b)
- Baldwin, B. G. 2000. New combinations and new genera in North America tarweeds (Compositae-Madiinae). Novon 9:462-471.
- Barbour, M. G., A. I. Solomeshch, and J. J. Buck. 2007b. Classification, ecological characterization, and presence of listed plant taxa of vernal pool associations in California. Report to USDI, Fish and Wildlife Service, Agreement Study No. 814205G238. University of California, Davis. 117 pp. plus 5 tables. [http://www.vernalpools.org/documents/Barbour_et_al_2007.pdf]
- Baye, P. R., P. M. Faber, and B. Grewell. 2000. Tidal marsh plants of the San Francisco estuary. Pages 9-33 in: P. R. Olofson, editor. Baylands ecosystem species and community profiles: Life histories and environmental requirements of key plants, fish and wildlife. San Francisco Bay Area Wetlands Ecosystem Goals Project, San Francisco Bay Regional Water Quality Control Board, Oakland, CA.
- CNPS [California Native Plant Society]. 2015-2017. A manual of California vegetation [online]. California Native Plant Society, Sacramento, CA. [http://vegetation.cnps.org/].
- Faber-Langendoen, D., J. Drake, M. Hall, G. Kittel, S. Menard, C. Nordman, M. Pyne, M. Reid, M. Russo, K. Schulz, L. Sneddon, K. Snow, and J. Teague. 2013-2019b. Screening alliances for induction into the U.S. National Vegetation Classification: Part 1 - Alliance concept review. NatureServe, Arlington, VA.
- Holland, R. F. 1986b. Preliminary descriptions of the terrestrial natural communities of California. Unpublished report prepared for the California Department of Fish and Game, Nongame-Heritage Program and Natural Diversity Database, Sacramento. 156 pp.
- Klein, A., and J. Evens. 2006. Vegetation alliances of western Riverside County, California. Contract Number: P0185404. Final report prepared for The California Department of Fish and Game, Habitat Conservation Division. California Native Plant Society, Sacramento, CA. 332 pp. [http://www.dfg.ca.gov/biogeodata/vegcamp/pdfs/VegMappingRpt_Western_Riverside.pdf]
- Munz, P. A. 1959. A California flora and supplement. University of California Press, Berkeley, CA. 1681 pp. plus 224 pp (supplement).
- Sawyer, J. O., T. Keeler-Wolf, and J. Evens. 2009. A manual of California vegetation. Second edition. California Native Plant Society, Sacramento CA. 1300 pp.
- Sawyer, J. O., and T. Keeler-Wolf. 1995. A manual of California vegetation. California Native Plant Society, Sacramento. 471 pp.
- Webster, L. 1981. Composition of native grasslands in the San Joaquin Valley, California. Madroño 28:231-241.