Astragalus musiniensis

Astragalus musiniensis is a perennial forb occurring on fine-textured substrates in desert shrub, mixed desert shrub, and pinyon-juniper communities of the western United States; in Emery, Carbon, Garfield, Grand, Kane, Sevier and Wayne counties of Utah, and Mesa and Garfield counties of western Colorado. There are an estimated 34 to 78 occurrences of this species, which are likely threatened by grazing, wildfire, energy production, roads, invasive species, off-road vehicles, and climate change and drought. Little is known about rangewide threats and trends, and monitoring populations is important to improving our understanding of the status of Astragalus musiniensis.

Astragalus musiniensis occurs in the western United States, where it is known from Emery, Carbon, Garfield, Grand, Kane, Sevier and Wayne counties of central and south-central Utah, and two counties in western Colorado (Mesa and Garfield) (FNA 2023). Range extent was estimated using herbarium specimens, photo-based observations, and NatureServe Network occurrence data collected between 1994 and 2025 (GBIF 2025, iNaturalist 2025, NatureServe 2025, RARECAT 2025, SEINet 2025).

By applying a 1 km separation distance to herbarium specimens, photo-based observations, and NatureServe Network occurrence data documented between 1994 and 2025, it is estimated that there are 78 occurrences rangewide (GBIF 2025, iNaturalist 2025, NatureServe 2025, RARECAT 2025, SEINet 2025). As of 2023, the Colorado Natural Heritage Program tracks six known occurrences documented in the Colorado Natural Heritage Program database, though two of these are historical (CNHP 2023). The Utah Natural Heritage Program estimates that there are 30 occurrences of this species using a 2 km separation distance and excluding historical observations over 40 years old (UNHP 2024).

Threats to Astragalus musiniensis are not well documented (Colorado Natural Heritage Program 2015, UNHP 2024). Potential threats to this species rangewide include impacts from habitat degradation due to grazing, wildfire, energy production (oil and gas development as well as renewable energy), roads, invasive species, off-road vehicles, and long-term drought.

Threats to Utah occurrences were compiled using observations and notes from Utah Rare Plant Database (2024) and Utah Geospatial Resource Center GIS Data (2024). The severity of impacts are not well known, so ranges are provided where appropriate. The majority of occurrences of Astragalus musiniensis reported in Utah within the last 40 years occur within boundaries of cattle grazing allotments, although it is unknown if cattle have access to these areas, or what impact they have in disturbing this species' habitat. One occurrence is within the boundaries of a past wildfire, although the impacts of fire and fire suppression on this occurrence are unknown. One occurrence is near an area which has the potential for wind energy development in the near future, three occurrences are near a potential solar energy development zone, and one occurrence is near a potential energy transmission line. One occurrence is near a past mineral producer, five occurrences are near gas wells, two are near gas fields, four are near permitted coal mining areas, and five are near coal leases. Forty two occurrences are located near Utah roads, although only 21 of these are major roads, and 16 are near trails and pathways. Additionally, one occurrence is near an electrical utilities line. Colorado occurrences are largely lacking threats information, though at least one population is threatened by livestock grazing, off-road vehicle use, and invasive plants including Bromus tectorum (NatureServe 2025). Long-term drought and climate change is also a threat which is likely impacting Astragalus musiniensis throughout its range (Wrobleski et al. 2023).