Deseret Milkvetch

Scientific Name: Astragalus desereticus Barneby

Plant Guide

Uses

There are no known human uses of Deseret milkvetch. This species appears to be non toxic to cattle, and though not considered primary forage, it may be inadvertently grazed along with other food sources (USDI-FWS, 1999).

Status

Deseret milkvetch was considered extinct for decades until its rediscovery in 1981. It is known from a single population in Utah County, Utah. Deseret milkvetch was listed in 1999 by the Fish and

Wildlife

Service as threatened (USDI-FWS, 1999). In 2007, the Fish and Wildlife Service gave advanced notice of intention to remove Deseret milkvetch from the list of endangered and threatened plants in the near future (USDI-FWS, 2007). It was determined that previous threats were not as significant as once believed, and that the species is not likely to become in danger of extinction throughout all or a significant portion of its range in the foreseeable future. Surveys conducted in 2006 indicated that the known population had increased by 31 percent since the time of listing (USDI-FWS, 2007). Consult the PLANTS Web site and your State Department of Natural Resources for this plant’s current status (e.g., threatened or endangered species, state noxious status, and wetland indicator values).

Description

General: Legume family (Fabaceae). Deseret milkvetch is a short-lived perennial forb rising from a subterranean caudex. The leaves are 4 to 12 cm (1.6 to 4.7 in) long with 11 to 17 leaflets, each being 2 to 14 mm (0.08 to 0.6 in) long and 1.5 to 8 mm (0.06 to 0.3 in) wide. The leaves and stems are hairy. The inflorescence is a 5 to 10 flowered raceme. The flowers are whitish with pale purple wings and a purple-tipped keel. The fruit is a densely hairy, curved, oval pod, 10 to 20 mm (0.4 to 0.8 in) long and 5 to 10 mm (0.2 to 0.4 in) thick (Welsh et al., 2003). Distribution: Deseret milkvetch is known from a single location in Utah County, Utah in the Thistle Creek watershed east of Birdseye, Utah. The total occupied area covers approximately 345 acres (USDI-FWS, 2007). For current distribution, consult the Plant Profile page for this species on the PLANTS Web site. Habitat: Desert milkvetch is restricted to steep, sandy, west and south facing slopes of the Moroni Formation at elevations from 1,645 to 1,700 m (5,400 to 5,600 ft). The associated vegetation is an open pinyon-juniper community with sagebrush (Artemisia tridentata), bitterbrush (Purshia tridentata), Indian ricegrass (Achnatherum hymenoides) and needle-and-thread (Stipa comata).

Adaptation

This species is endemic to sandy-gravelly soils weathered from conglomerate outcrops of the Moroni Formation (USDI-FWS, 2007). The mean annual precipitation for the population is 30 to 35 cm (12 to 14 in) (Western Regional Climate Center, 2010).

Management

This species was listed as threatened due to its restricted population size and several potential threats to its habitat, Those threats included rural development, cattle grazing and impacts to pollinator habitat, Since listing, the population has grown considerably and the threats do not appear as significant as earlier believed, Approximately 67 percent of the species’ range is managed by the Utah Department of Wildlife Resources as part of the Northwest Manti Wildlife Management Area, Use soil moisture sensors to measure the soil moisture of Deseret Milkvetch., UTDWR management provides protection against anticipated threats, thus mitigating concern for the species,

Pests and Potential Problems

There are no known pests or potential problems regarding Deseret milkvetch.

Environmental Concerns

Concerns

Concerns

There are no known environmental concerns regarding Deseret milkvetch.

Seeds and Plant Production

Plant Production

Plant Production

Deseret milkvetch flowers and sets seed in May and June. Its primary pollinators are believed to be bumblebees or other pollen generalist bee species (CPC, 2010).