''Astragalus amphioxys'', common name crescent milkvetch, is a plant found in the

American southwest The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that generally includes Arizona, New Mexico, and adjacent portions of California, Colorado ...

, including the whole of Utah, the southeast part of Nevada, the north part of Arizona, the western part of Colorado, the northwestern part of New Mexico, and one county in Texas. It was first described by Asa Gray in 1878.

Description

The color of the flowers ranges from pink-purple to reddish-purple. The irregular flowers are in elongated clusters. The bloom period is between the months of March to June. It rarely flowers in its first year of life. The petals are around twice as long as the sepals. The leaf color is green to silvery-white. The compound leaves are round or oval in shape. The smooth leaves have an alternate leaf attachment. The spineless leaves and stem have hair on them. They have the same amount of hair on opposite sides. The fruits are pods. The pods only have one chamber and an lower seam that lies in a groove, distinguishing it from other similar species. It is most commonly found in the months of April, May, and June. Astragalus amphioxys has 4 subspecies: Astragalus amphioxys var. amphioxys native to Nevada, Utah, Arizona, and New Mexico, secure in all four. Astragalus amphioxys var. modestus native to Nevada, Utah, and Arizona, critically endangered. Astragalus amphioxys var. musimonum native to Nevada and Arizona, imperiled in Nevada and critically endangered in Arizona. Astragalus amphioxys var. vespertinus native to Nevada, Utah, Arizona, Colorado, and New Mexico.

Distribution and habitat

It can be found in deserts, arid grasslands, and among piñon and juniper. It occurs in the Desert Scrub, Interior Chaparral, Semidesert Grasslands, Pinyon Juniper Woodland, and Montane Conifer Forest plant communities, at elevations of 2000–7000 feet. Although most of the observations of the species were in the general range that the species is known for (I.e. Southwestern U.S.), according to GBIF.org, there was one observation of it in Northeastern Alaska. It can be found in

Arches National Park Arches National Park is a national park in eastern Utah, United States. The park is adjacent to the Colorado River, north of Moab, Utah. More than 2,000 natural sandstone arches are located in the park, including the well-known Delicate Arch, ...

, specifically around the visitor center and on the Portal trail outside the park. It has a global rank of G5, which means it is very secure. Arizona and Nevada rank it as secure, but Texas ranks it as very endangered in the state. All of the other states don't have a rank for their state.

Uses

The Zuni use the plant medicinally. The fresh or dried root is chewed by a medicine man before sucking snakebite and poultice applied to wound.

References

amphioxys Flora of the Southwestern United States Plants used in traditional Native American medicine {{medicinal-plant-stub