Print Report

A4173 Layia fremontii - Achyrachaena mollis Vernal Pool Alliance

Type Concept Sentence: Achyrachaena mollis and/or Layia fremontii are characteristically present in the herbaceous layer. This alliance occurs in California at 15-710 m elevation in short-inundated, shallow, flashy vernal hardpan pools and mesic meadows with subsurface waterflow in winter and early spring. Soils are shallow and rocky.

Common (Translated Scientific) Name: Fremont''s Tidy-tips - Blow-wives Vernal Pool Alliance

Colloquial Name: Fremont''s Tidy-tips - Blow-wives Vernal Pool

Hierarchy Level:  Alliance

Type Concept: This alliance consists of intermittent to continuous cover of herbs <50 cm in height. Achyrachaena mollis and/or Layia fremontii are characteristically present in the herbaceous layer with Blennosperma nanum, Brodiaea minor, Chlorogalum angustifolium, Cicendia quadrangularis, Clarkia purpurea, Dodecatheon clevelandii ssp. patulum, Downingia cuspidata, Downingia ornatissima, Hemizonia fitchii, Lasthenia californica, Lasthenia fremontii, Lepidium nitidum, Limnanthes douglasii ssp. rosea, Leptosiphon parviflorus, Microseris acuminata, Navarretia tagetina, Plagiobothrys austiniae, Plagiobothrys greenei, Plantago erecta, Taeniatherum caput-medusae, Trifolium depauperatum, Triphysaria eriantha ssp. eriantha, and Vulpia microstachys. This alliance occurs in California at 15-710 m elevation in short-inundated, shallow, flashy vernal hardpan pools and mesic meadows with subsurface waterflow in winter and early spring. Soils are shallow and rocky.

Diagnostic Characteristics: Achyrachaena mollis, Clarkia purpurea, Layia fremontii, Taeniatherum caput-medusae, and/or Triphysaria eriantha ssp. eriantha are present as diagnostic species in the herbaceous layer; other diagnostic vernal pool species may be present such as Lasthenia fremontii (Barbour et al. 2007b).

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Barbour et al. (2003, 2007b) recognized the Downingia-Lasthenia class for California vernal pool vegetation on all geomorphic surfaces, landscapes, and soil types in the Central Valley and adjacent foothills. Within that class, they recognized this alliance for vegetation of comparative shallow vernal pools and of pool edges.

This alliance has a similar inundation pattern to ~Montia fontana - Sidalcea calycosa Vernal Pool Alliance (A4174)$$ and Trifolium variegatum Vernal Pool Alliance (A4175)$$ and commonly occurs on substrates derived from metamorphic or volcanic material. However, it is not found on basalt flows of table mountains. Some of these stands are just slightly moister than the surrounding uplands and occupy the transition between vernal pools or swales and uplands.

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

Floristics: This alliance consists of intermittent to continuous cover of herbs <50 cm in height. Achyrachaena mollis and/or Layia fremontii are characteristically present in the herbaceous layer with Blennosperma nanum, Brodiaea minor, Chlorogalum angustifolium, Cicendia quadrangularis, Clarkia purpurea, Dodecatheon clevelandii ssp. patulum, Downingia cuspidata, Downingia ornatissima, Hemizonia fitchii (= Centromadia fitchii), Lasthenia californica, Lasthenia fremontii, Lepidium nitidum, Limnanthes douglasii ssp. rosea, Leptosiphon parviflorus, Microseris acuminata, Navarretia tagetina, Plagiobothrys austiniae, Plagiobothrys greenei, Plantago erecta, Taeniatherum caput-medusae, Trifolium depauperatum, Triphysaria eriantha ssp. eriantha, and Vulpia microstachys.

Dynamics:  No Data Available
Environmental Description:  This alliance occurs in California at 15-710 m elevation in short-inundated, shallow, flashy vernal hardpan pools and mesic meadows with subsurface waterflow in winter and early spring. Soils are shallow and rocky.
Geographic Range: This alliance is found in the Great Central Valley and Sierra Nevada foothills of California.

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.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 A4173 Fremont''s Tidy-tips - Blow-wives Vernal Pool Alliance A4173 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: = Layia fremontii - Achyrachaena mollis (Fremont''s tidy-tips - Blow wives vernal pools) Alliance (Sawyer et al. 2009) [42.002.00]
< Northern Hardpan Vernal Pool (#44110) (Holland 1986b)
< Northern hardpan vernal pool habitat (Sawyer and Keeler-Wolf 1995)
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
  • Barbour, M. G., A. I. Solomeshch, R. F. Holland, C.W. Witham, R. L. Macdonald, S. S. Cilliers, J. A. Molina, J. J. Buck, and J. M. Hillman. 2005. Vernal pool vegetation of California: Communities of long-inundated deep habitats. Phytocoenologia 35:177-200.
  • 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]
  • Barbour, M. G., A. Solomeshch, C. Witham, R. Holland, R. Macdonald, S. Cilliers, J. A. Molina, J. Buck, and J. Hillman. 2003. Vernal pool vegetation of California: Variation within pools. Madroño 50:129-146.
  • 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. 1976. The vegetation of vernal pools: A survey. Pages 11–15 in: S. Jain, editor. Vernal pools, their ecology and conservation. Publication Number 9. Institute of Ecology, University of California, Davis, CA.
  • 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.
  • Keeler-Wolf, T., D. R. Elam, K. Lewis, and S. A. Flint. 1998b. California vernal pool assessment. Preliminary report. California Department of Fish and Game, Sacramento, CA.
  • Klein, A., J. Crawford, J. Evens, T. Keeler-Wolf, and D. Hickson. 2007. Classification of the vegetation alliances and associations of the northern Sierra Nevada foothills, California. Volumes 1 and 2. Report prepared for California Department of Fish and Game, Habitat Conservation Division. California Native Plant Society, Sacramento, CA. [https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=18232&inline=1]
  • 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.