Ash Meadows Milk-vetch

views updated

Ash Meadows Milk-vetch

Astragalus phoenix

StatusThreatened
ListedMay 20, 1985
FamilyLeguminosae (Fabaceae)
DescriptionLow-growing, mat-forming perennial with clusters of pink or purple flowers.
HabitatAsh Meadows; dry saline slopes in clay soils.
ThreatsRestricted range, agricultural development, groundwater pumping.
RangeNevada

Description

Ash meadows milk-vetch, Astragalus phoenix, is a low-growing perennial that forms mats about 20 in (51 cm) across. It produces a terminal cluster (an inflorescence) of several pink or purple flowers on a short erect stalk. Flowers are very tiny, only about 0.1 in (2.5 mm) long.

Habitat

The Ash Meadows milk-vetch requires undisturbed, unplowed, arid, highly alkaline soils.

Distribution

Low numbers of milk-vetch plants are widely scattered over the eastern portion of Ash Meadows in Nye County, Nevada. Numbers fluctuate widely from year to year but declined steadily beginning in the mid-1970s.

Threats

Always relatively rare, this milk-vetch suffered further decline because of the agricultural development of portions of Ash Meadows.

Conservation and Recovery

This species was greatly reduced in numbers in the late twentieth century through the loss of habitat, caused primarily by cropland development and peat mining. Carson Slough, an extensive marsh, was destroyed by peat mining in the early 1960s. Roads were built through plant habitat, and many thousands of acres were cleared and plowed for crop production. Aquatic environments were degraded by groundwater pumping and diversion of water for irrigation.

Critical habitat was designated for this species to consist of about 1,200 acres (486 hectares) in the Nevada portion of Ash Meadows.

About 40% of the habitat occupied by the Ash Meadows milk-vetch is within the Ash Meadows National Wildlife Refuge. Conservation management of the 11,000-acre (4,450-hectare) preserve will greatly enhance the prospects for recovery of the plant, along with many other vulnerable endemics.

Contact

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
Telephone: (503) 231-6121
http://pacific.fws.gov/

References

Barneby, R. C. 1970. "A New Astragalus (Fabaceae) from Nevada." Madrono 20: 395-398.

Mozingo, H. N., and M. Williams. 1980. "Rare and Endangered Plants of Nevada." U. S. Fish and Wildlife Service, Portland, Oregon, and U. S. Bureau of Land Management, Reno, Nevada.

Sada, D. W. 1984. "Ash Meadows, Nye County, Nevada, Land Protection Plan." U. S. Fish and Wildlife Service, Portland, Oregon.

More From encyclopedia.com