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Home/Species/ Ash Valley milk-vetch

Astragalus anxius

Meinke & Kaye

Ash Valley milk-vetch

G1Critically Imperiled Found in 1 roadless area NatureServe Explorer →
G1Critically ImperiledGlobal Rank
High - mediumThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.130599
Element CodePDFAB0FBD0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single state or province
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderFabales
FamilyFabaceae
GenusAstragalus
Other Common Names
Lassen Milkvetch (EN) Troubled Milkvetch (EN) troubled milkvetch (EN)
Concept Reference
Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.
Conservation Status
Rank Method Rank calculation - Biotics v2
Review Date2013-08-12
Change Date1997-03-17
Edition Date2024-05-31
Edition Authorsrev. A. Olivero (2003), rev. R. Bittman (2013), J. Johnson (2024)
Threat ImpactHigh - medium
Range Extent250-1000 square km (about 100-400 square miles)
Number of Occurrences6 - 20
Rank Reasons
Astragalus anxius is endemic to Lassen and Modoc Counties, California, USA. This species in known from 16 occurrences in arid flats with sagebrush, juniper and pine woodlands, and sparse pine forests (Isely 1998, CNDDB 2024). Some occurrences are threatened by livestock trampling, grazing, ORV use and roads and all occurrences are threatened by increased droughts caused by climate change.
Range Extent Comments
Endemic to Lassen County, California, USA. Range extent was estimated using herbarium specimens, photo-based observations, and NatureServe Network occurrence data collected between 1993 and 2024 (iNaturalist 2024, CNDDB 2024).
Occurrences Comments
By applying a 1 km separation distance to herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1993 and 2024, it is estimated that there are 17 occurrences range-wide (iNaturalist 2024, CNDDB 2024).
Threat Impact Comments
Most occurrences are subject to trampling from livestock grazing. Motorized trails and roads are also mentioned at some sites.
Ecology & Habitat

Habitat

Astragalus anxius grows on dry, gravelly, volcanic tuff soil among pines and sagebrush from 1500 to 1800 m elevation (CNDDB 2024).
Terrestrial Habitats
Forest/WoodlandForest - ConiferWoodland - ConiferShrubland/chaparral
Other Nations (1)
United StatesN1
ProvinceRankNative
CaliforniaS1Yes
Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)Yes
Roadless Areas (1)
California (1)
AreaForestAcres
Knox Mtn.Modoc National Forest5,975
References (7)
  1. California Department of Fish and Game. 2000. Natural Diversity Database (RareFind 2), Version 2.1.2, January 25, 2000. Downloaded in 2003.
  2. California Native Plant Society (CNPS). 2001. Inventory of Rare and Endangered Plants of California (sixth edition). Rare Plant Scientific Advisory Committee, David P. Tibor, Convening Editor. California Native Plant Society. Sacramento, CA. x + 388pp.
  3. California Natural Diversity Database (CNDDB). 2013. RareFind Version 4. California Department of Fish and Game, Sacramento.
  4. California Natural Diversity Database (CNDDB). 2024. RareFind Version 5.3.0. California Department of Fish and Game, Sacramento.
  5. iNaturalist. 2024. Online. Available: https://www.inaturalist.org (accessed 2024).
  6. Isely, D. 1998. Native and naturalized Leguminosae (Fabaceae) of the United States (exclusive of Alaska and Hawaii). Monte L. Bean Life Science Museum, Brigham Young University; MLBM Press, Provo, Utah. 1007 pp.
  7. Kartesz, J.T. 1994. A synonymized checklist of the vascular flora of the United States, Canada, and Greenland. 2nd edition. 2 vols. Timber Press, Portland, OR.