Astragalus applegatei
M.E. Peck
Applegate's Milkvetch
G1Critically ImperiledGlobal Rank
Very highThreat Impact
U.S. Fish & Wildlife Service, https://www.usa.gov/government-works
Identity
Unique IDELEMENT_GLOBAL.2.156762
Element CodePDFAB0F0P0
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVascular Plant
Endemicendemic to a single state or province
KingdomPlantae
PhylumAnthophyta
ClassDicotyledoneae
OrderFabales
FamilyFabaceae
GenusAstragalus
Other Common Names
Applegate's 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 Date2024-06-03
Change Date1984-07-16
Edition Date2024-06-03
Edition AuthorsRoth, E.; rev. E. Joyal, Maybury/Vrilakas, 1996, B. MacBryde 9/2000, rev. L.K. Wise (2012), J. Johnson (2024)
Threat ImpactVery high
Range Extent<100 square km (less than about 40 square miles)
Number of Occurrences1 - 5
Rank Reasons
Astragalus applegatei is a perennial herb that has a limited range (Klamath County, Oregon, USA) with a small number of extant populations and recent loss of populations. It is threatened by fragmentation and loss of habitat, urban development, road and pipeline construction, conversion of habitat for agriculture, elimination of the natural seasonal flooding regime along the floodplains supporting the species, suppression of fire, invasive exotic plants, and insect usage. Two sites are threatened by rabbit grazing.
Range Extent Comments
Astragalus applegatei occurs in the western United States and is only found in the Lower Klamath Basin, near the city of Klamath Falls, in Klamath County, Oregon. Barneby (1964) suggested that the plant may also occur in adjacent Siskiyou County, California, but it has never been reported from California. Range extent was estimated using herbarium specimens and NatureServe Network occurrence data collected between 1993 and 2024 (OSU 2024, NatureServe 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 five extant occurrences range-wide (OSU 2024, NatureServe 2024).
Threat Impact Comments
The habitat of Astragalus applegatei is altered by agriculture and urban development with most occurrences on private land or the regional airport. Maintenance activities around the airport along with chemical spills and airborne pollution may affect the plants, but this area is also protected from other types of disturbance. Rabbit grazing, insect damage, competition from native shrubs, and invasive plants are noted at most occurrences. A lack of flooding due to dam management prevents habitat renewing processes such as silt deposition and elimination of competing vegetation; fire suppression also prevents fires from removing competing vegetation. Populations west of the Klamath River will be impacted by the construction of the Pacific Connector/Jordan Cove natural gas pipeline. The climate change vulnerability index is calculated as highly vulnerable to climate change (NatureServe 2024).
Ecology & Habitat
Description
Astragalus applegatei is a low lying perennial, herbaceous plant with slender stems appearing clustered or loosely spreading from a taproot. Mature plants may grow as a circular mat with a radius of 1-3 feet (1/3 - 1 m). Flowers are pea-like, light purple, about 1/4 inch (.6 cm) long with the lower petal almost pependicular to the flower stalk. Seed pods are about 1/3-1/2 inch (.8 - 1.25 cm) long with purple mottling.
Habitat
Astragalus applegatei grows in flat, seasonally moist remnants of alkaline floodplain grasslands of the Klamath Basin, at about 1250 meters. The substrate is poorly drained fine silt loam (an underlying hardpan impedes drainage). Prior to irrigation and water control along the Klamath River, periodic flooding probably limited the dominance of other species and provided openings for the establishment of Astragalus applegatei (OSU 2024, NatureServe 2024).
Reproduction
Self-fertilization and crossing occur (Recovery Plan 1998).
Terrestrial Habitats
Grassland/herbaceousCropland/hedgerow
Palustrine Habitats
HERBACEOUS WETLANDRiparian
Other Nations (1)
United StatesN1
| Province | Rank | Native |
|---|---|---|
| Oregon | S1 | Yes |
Threat Assessments
| Threat | Scope | Severity | Timing |
|---|---|---|---|
| 1 - Residential & commercial development | Large (31-70%) | Extreme - serious | High - low |
| 2 - Agriculture & aquaculture | Large (31-70%) | Extreme - serious | High (continuing) |
| 2.1 - Annual & perennial non-timber crops | Large (31-70%) | Extreme - serious | High (continuing) |
| 4 - Transportation & service corridors | Large (31-70%) | Extreme - serious | High - low |
| 4.1 - Roads & railroads | Restricted (11-30%) | Extreme - serious | High - low |
| 4.2 - Utility & service lines | Restricted (11-30%) | Serious or 31-70% pop. decline | Moderate (short-term) |
| 4.4 - Flight paths | Large (31-70%) | Serious - moderate | High (continuing) |
| 7 - Natural system modifications | Pervasive (71-100%) | Extreme - serious | High (continuing) |
| 7.1 - Fire & fire suppression | Pervasive (71-100%) | Extreme - serious | High (continuing) |
| 7.2 - Dams & water management/use | Pervasive (71-100%) | Extreme - serious | High (continuing) |
| 8 - Invasive & other problematic species, genes & diseases | Pervasive (71-100%) | Extreme - serious | High (continuing) |
| 8.1 - Invasive non-native/alien species/diseases | Pervasive (71-100%) | Extreme - serious | High (continuing) |
| 8.2 - Problematic native species/diseases | Pervasive (71-100%) | Extreme - serious | High (continuing) |
| 9 - Pollution | Large (31-70%) | Serious - moderate | High (continuing) |
Plant Characteristics
DurationPERENNIAL
Economic Value (Genus)Yes
Roadless Areas (1)
South Dakota (1)
| Area | Forest | Acres |
|---|---|---|
| Indian Creek | Buffalo Gap National Grassland | 24,666 |
References (6)
- Barneby, R.C. 1964. Atlas of North American Astragalus. 2 Vols. New York Botanical Garden, Bronx, New York. 1188 pp.
- 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.
- 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.
- NatureServe. 2024. NatureServe Network Biodiversity Location Data. NatureServe, Arlington, Virginia.
- Oregon State University (OSU). 2024. Oregon Flora website. Oregon State University Herbarium at Oregon State University. Online. Available: https://oregonflora.org/ (accessed 2024).
- Parenti, R. 1993. Endangered and threatened wildlife and plants; Determination of endangered status for the plant Astragalus applegatei (Applegate's milk-vetch). Federal Register 58(143): 40547-40551.