Print Report

A4171 Hemizonia fasciculata Meadow Alliance

Type Concept Sentence: Hemizonia fasciculata is codominant or conspicuous in the herbaceous layer. The alliance occurs on clay flats and bottomlands, edges of vernal pools, shallow pools, and alkaline flats at 0-900 m elevation in southern California.

Common (Translated Scientific) Name: Clustered Tarweed Meadow Alliance

Colloquial Name: Clustered Tarweed Meadow

Hierarchy Level:  Alliance

Type Concept: This alliance consists of open to continuous cover of herbs <1 m in height. Hemizonia fasciculata is codominant or conspicuous in the herbaceous layer with Amsinckia menziesii, Atriplex argentea, Atriplex coronata var. notatior, Centaurea melitensis, Centaurea solstitialis, Corethrogyne filaginifolia, Cressa truxillensis, Deschampsia danthonioides, Erodium cicutarium, Frankenia salina, Hirschfeldia incana, Hordeum depressum, Hordeum intercedens, Hordeum murinum, Lasthenia californica, Lasthenia fremontii, Marrubium vulgare, Mesembryanthemum nodiflorum, Plagiobothrys spp., and Trifolium spp. Emergent shrubs may be present at low cover, including Artemisia californica, Eriogonum fasciculatum, Gutierrezia spp., Hazardia squarrosa, or Suaeda moquinii. The alliance occurs on clay flats and bottomlands, edges of vernal pools, shallow pools, and alkaline flats at 0-900 m elevation in southern California. Soils are subjected to periodic or intermittent inundation, are poorly drained fine-textured alluvium, and may be underlain by claypan or other impervious layer.

Diagnostic Characteristics: Hemizonia fasciculata >30% relative cover or seasonally present in the herbaceous layer with a variety of other annuals (Klein and Evens 2006).

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Klein and Evens (2006) considered some stands close to Amsinckia (menziesii, tessellata) and other upland herb alliances and other stands close to ~Centromadia pungens - Hemizonia sp. Vernal Pool Alliance (A4170)$$ and other vernal pool alliances. Barbour et al. (2007b) suggested that Hemizonia fasciculata was an indicator of southern California vernal pools, but their stands were less alkaline and contained few halophytes. Further sampling and analysis are needed to better understand the herbaceous vegetation and vernal pool patterns involving Amsinckia menziesii, Brodiaea orcuttii, Centromadia spp., Hemizonia fasciculata, Eryngium aristulatum var. parishii, Orcuttia californica, and Pogogyne abramsii in southern California.

Similar NVC Types: No Data Available
note: No Data Available
Physiognomy and Structure: No Data Available

Floristics: This alliance consists of open to continuous cover of herbs <1 m in height. Hemizonia fasciculata (= Deinandra fasciculata) is codominant or conspicuous in the herbaceous layer with Amsinckia menziesii, Atriplex argentea, Atriplex coronata var. notatior, Centaurea melitensis, Centaurea solstitialis, Corethrogyne filaginifolia, Cressa truxillensis, Deschampsia danthonioides, Erodium cicutarium, Frankenia salina, Hirschfeldia incana, Hordeum depressum, Hordeum intercedens, Hordeum murinum, Lasthenia californica, Lasthenia fremontii, Marrubium vulgare, Mesembryanthemum nodiflorum, Plagiobothrys spp., and Trifolium spp. Emergent shrubs may be present at low cover, including Artemisia californica, Eriogonum fasciculatum, Gutierrezia spp., Hazardia squarrosa, or Suaeda moquinii.

Dynamics:  Native Americans probably burned this vegetation historically at different frequencies throughout California. Although little is known about fire returns for this and other native annual vegetation types in cismontane California (Wills 2006), seed banks and annual habit of the diagnostic species likely enable high fire return intervals. Keeley (2002) suggested that burning occurred in higher frequency adjacent to long-term occupation sites, and Anderson (2005) suggested that many annual plants benefited from tending by Native Americans.
Environmental Description:  The alliance occurs on clay flats and bottomlands, edges of vernal pools, shallow pools, and alkaline flats at 0-900 m elevation in southern California. Soils are subjected to periodic or intermittent inundation, are poorly drained fine-textured alluvium, and may be underlain by claypan or other impervious layer.
Geographic Range: This alliance is found in southern California mountains and valleys.

Nations: US

States/Provinces:  CA


Confidence Level: Low - Poorly Documented

Confidence Level Comments: No Data Available
Grank: G3?

Greasons: No Data Available
Type Name Database Code Classification Code
Class 2 Shrub & Herb Vegetation Class C02 2
Subclass 2.B Temperate & Boreal Grassland & Shrubland Subclass S18 2.B
Formation 2.B.1 Mediterranean Scrub & Grassland Formation F038 2.B.1
Division 2.B.1.Na Californian Scrub & Grassland Division D327 2.B.1.Na
Macrogroup 2.B.1.Na.3 Purple Needlegrass - Harvest Brodiaea - Rusty Popcorn-flower Native Grassland Macrogroup M045 2.B.1.Na.3
Group 2.B.1.Na.3.a Californian Annual Grassland & Forb Meadow Group G766 2.B.1.Na.3.a
Alliance A4171 Clustered Tarweed Meadow Alliance A4171 2.B.1.Na.3.a
Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available
Synonomy: = Deinandra fasciculata (Clustered tarweed fields) Alliance (Sawyer et al. 2009) [44.161.00]
= Deinandra fasciculata Herbaceous Alliance (CNPS 2017) [44.161.00]
>< California Annual Grassland Series (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)
Concept Author(s): J.O. Sawyer et al. (2009)

Author of Description: M.J. Russo after Sawyer et al. (2009)

Acknowledgements: No Data Available

Version Date: 02-21-15
  • Anderson, M. K. 2005. Tending the wild: Native American knowledge and the management of California''s natural resources. University of California Press, Berkeley, CA.
  • Baldwin, B. G. 2000. New combinations and new genera in North America tarweeds (Compositae-Madiinae). Novon 9:462-471.
  • 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.
  • Keeley, J. E. 2002. Native American impacts on fire regimes of the California coastal ranges. Journal of Biogeography 29:303-320.
  • 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]
  • 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.
  • Wills, R. 2006. Central Valley bioregion. Pages 295-320 in: N. G. Sugihara, J. W. van Wagtendonk, K. E. Shaffer, J. Fites-Kaufman, and A. E. Thode, editors. Fire in California''s ecosystems. University of California Press, Berkeley.