Astragalus phoenix is a rare species of milkvetch

Astragalus

Astragalus is a large genus of about 3,000 species of herbs and small shrubs, belonging to the legume family Fabaceae, subfamily Faboideae. The genus is native to temperate regions of the Northern Hemisphere...

 known by the common name Ash Meadows milkvetch. It is endemic to Ash Meadows

Ash Meadows National Wildlife Refuge

The Ash Meadows National Wildlife Refuge is a protected wildlife refuge, administered by the U.S. Fish and Wildlife Service, located west-northwest of Las Vegas, Nevada, in southern Nye County...

, a desert oasis

Oasis

In geography, an oasis or cienega is an isolated area of vegetation in a desert, typically surrounding a spring or similar water source...

 and wildlife refuge

Wildlife refuge

A wildlife refuge, also called a wildlife sanctuary, may be a naturally occurring sanctuary, such as an island, that provides protection for species from hunting, predation or competition, or it may refer to a protected area, a geographic territory within which wildlife is protected...

 in Nye County, Nevada

Nye County, Nevada

-National protected areas:* Ash Meadows National Wildlife Refuge* Death Valley National Park * Humboldt-Toiyabe National Forest * Spring Mountains National Recreation Area -Demographics:...

, near the California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 border. It is one of several rare plants and animals endemic to the area. The habitat is made up of stark, white flats

Sink (geography)

A geographic sink is a depression within an endorheic basin where water collects with no visible outlet. Instead of discharging, the collected water is lost due to evaporation and/or penetration...

 and washes

Arroyo (creek)

An arroyo , a Spanish word translated as brook, and also called a wash is usually a dry creek or stream bed—gulch that temporarily or seasonally fills and flows after sufficient rain. Wadi is a similar term in Africa. In Spain, a rambla has a similar meaning to arroyo.-Types and processes:Arroyos...

 in a wetland

Wetland

A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....

 area that is fed by springs

Spring (hydrosphere)

A spring—also known as a rising or resurgence—is a component of the hydrosphere. Specifically, it is any natural situation where water flows to the surface of the earth from underground...

 and undergoes evaporation

Evaporation

Evaporation is a type of vaporization of a liquid that occurs only on the surface of a liquid. The other type of vaporization is boiling, which, instead, occurs on the entire mass of the liquid....

, leaving behind a hard mineral crust on the land. The plant grows in undisturbed areas of the crust. It can be found at about 13 sites in a seven-by-three-mile range. It is a federally listed threatened species

Endangered species

An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

.

This plant is a perennial herb forming a flat cushion or mat up to half a meter wide. The inflorescence

Inflorescence

An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...

 bears one or two pink or purple flowers. Other plants occurring in the area include saltgrass (Distichlis spicata), shadscale

Atriplex confertifolia

Atriplex confertifolia is a species of evergreen shrub in the Chenopodiaceae family, which is native to the western United States.-Habitat:Shadscale is a common, often dominant, shrub in the lowest and driest areas of the Great Basin...

 (Atriplex confertifolia), and alkali goldenbush

Isocoma acradenia

Isocoma acradenia is a species of flowering plant in the daisy family known by the common name alkali goldenbush. It is native to the southwestern United States and Baja California, where it grows in arid, sandy areas, particularly mineral-rich areas such as alkali flats and gypsum soils.Isocoma...

 (Isocoma acradenia).

The plant is pollinated by bee

Bee

Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...

s of genus Anthophora

Anthophora

The bee genus Anthophora is one of the largest in the family Apidae, with over 450 species worldwide in 14 different subgenera. They are most abundant and diverse in the Holarctic and African biogeographic regions. All species are solitary, though many nest in large aggregations...

, which show an affinity for it even in the presence of other flowering plants.

Threats to this species include the destruction of or damage to its unique habitat. Alterations in the hydrology

Hydrology

Hydrology is the study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability...

 of the region occur when pumping or other processes affects the flow of the springs and seeps. Road

Road

A road is a thoroughfare, route, or way on land between two places, which typically has been paved or otherwise improved to allow travel by some conveyance, including a horse, cart, or motor vehicle. Roads consist of one, or sometimes two, roadways each with one or more lanes and also any...

 construction, mining

Mining

Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

 operations, and agriculture

Agriculture

Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

reduced the plant's numbers.