Home/Species/ Welsh's Milkvetch

Astragalus welshii

Barneby

Welsh's Milkvetch

G3Vulnerable Found in 7 roadless areas NatureServe Explorer →

G3VulnerableGlobal Rank

MediumThreat Impact

Identity

Unique IDELEMENT_GLOBAL.2.152558

Element CodePDFAB0FB20

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVascular Plant

Endemicendemic to a single state or province

KingdomPlantae

PhylumAnthophyta

ClassDicotyledoneae

OrderFabales

FamilyFabaceae

GenusAstragalus

Other Common Names

Loa milkvetch (EN) Loa 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 Date2023-02-01

Change Date2023-02-01

Edition Date2023-02-22

Edition AuthorsNiese, J., rev L. Broaddus, rev. L. Morse, rev. B. Franklin (1996), rev. A. Treher (2015, 2023)

Threat ImpactMedium

Range Extent5000-20,000 square km (about 2000-8000 square miles)

Number of Occurrences6 - 80

Rank Reasons

Astragalus welshii is a perennial herb that occurs in the western United States where it is endemic to the Southern Plateaus of Utah. There are 24 occurrences and the species is restricted to igneous gravels. Livestock trampling of plants and habitat may be the most widespread threat to this species, thus monitoring their impacts is necessary determine if grazing intensity needs to be adjusted.

Range Extent Comments

Astragalus welshii occurs in the western United States where it is endemic to the Southern Plateaus of Utah. It is documented in five counties: western Garfield, eastern Iron, Piute, Kane, southeastern Millard, and Wayne counties (Welsh et al. 2015). Range extent was estimated with data from Utah Rare Plant Database (UNHP 2022).

Occurrences Comments

A range is used in the factor score as some occurrences are older and need to be revisited.

Threat Impact Comments

Threats to this species are not well documented. Threats were compiled using observations and notes from Utah Rare Plant Database (2022) and Utah Geospatial Resource Center GIS Data (2022). Severity of impacts are not well known so ranges are provided where appropriate (UNHP 2022).

Almost all known occurrences are within active grazing allotments. Transmission lines cross occupied habitat near Sulpherdale and some occurrences near roads may be impacted by maintenance. Several occurrences are within UREZ phase 1 solar, geothermal, and wind zone areas and may be impacted by future renewable energy development (UNHP 2022).

Ecology & Habitat

Habitat

This species occurs exclusively on igneous gravels, in sagebrush, pinyon-juniper, and sagebrush-aspen communities at elevations of 2,000-2,810 m.

Terrestrial Habitats

Forest/WoodlandWoodland - HardwoodWoodland - ConiferShrubland/chaparral

Other Nations (1)

United StatesN3

Province	Rank	Native
Utah	S3	Yes

Threat Assessments

Threat	Scope	Severity	Timing
2 - Agriculture & aquaculture	Pervasive (71-100%)	Moderate or 11-30% pop. decline	High (continuing)
2.3 - Livestock farming & ranching	Pervasive (71-100%)	Moderate or 11-30% pop. decline	High (continuing)
2.3.4 - Scale unknown/unrecorded	Pervasive (71-100%)	Moderate or 11-30% pop. decline	High (continuing)
3 - Energy production & mining	Restricted (11-30%)	Unknown	Low (long-term)
3.3 - Renewable energy	Restricted (11-30%)	Unknown	Low (long-term)
4 - Transportation & service corridors	Restricted (11-30%)	Moderate - slight	High (continuing)
4.1 - Roads & railroads	Restricted (11-30%)	Moderate - slight	High (continuing)
4.2 - Utility & service lines	Small (1-10%)	Slight or 1-10% pop. decline	High (continuing)

Plant Characteristics

DurationPERENNIAL

Economic Value (Genus)Yes

Roadless Areas (7)

Utah (7)

Area	Forest	Acres
Boulder Mtn. / Boulder Top / Deer Lake	Dixie National Forest	110,690
Casto Bluff	Dixie National Forest	87,466
Deer Creek	Dixie National Forest	39,818
Little Creek	Fishlake National Forest	11,479
Long Neck Mesa / Steep Creek / Oak Creek - Steep Creek / Oak	Dixie National Forest	55,489
Signal Peak	Fishlake National Forest	30,889
Thousand Lake Mountain	Fishlake National Forest	27,267

References (8)

Albee, B.J., L.M. Shultz, and S. Goodrich. 1988. Atlas of the vascular plants of Utah. Utah Museum Natural History Occasional Publication 7, Salt Lake City, Utah. 670 pp.
Barneby, R.C. 1989. Fabales. In A. Cronquist, A.H. Holmgren, N.H. Holmgren, J.L. Reveal, and P.K. Holmgren (eds.). Intermountain flora: Vascular plants of the Intermountain West, U.S.A. Vol. 3, Part B. New York Botanical Garden, Bronx. 279 pp.
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.
Utah Geospatial Resource Center. 2022. Utah Geospatial Resource Center. Online. Available: https://gis.utah.gov/ (accessed 2022).
Utah Natural Heritage Program. 2022. Utah Rare Plant Database (accessed 2022).
Utah Natural Heritage Program (UNHP). 2022. Element Subnational Ranking Form: <i>Astragalus welshii</i> in Biotics 5 database. NatureServe, Arlington, Virginia (accessed 1 Feb 2023).
Welsh, S.L., N.D. Atwood, S. Goodrich, and L.C. Higgins (eds.) 1993. A Utah flora. 2nd edition. Brigham Young Univ., Provo, Utah. 986 pp.
Welsh, S.L., N.D. Atwood, S. Goodrich, and L.C. Higgins. (Eds). 2015. A Utah flora, fifth edition, revised 2015. Monte L. Bean Life Science Museum, Provo, Utah. 987 pp.

Astragalus welshii

Habitat

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