National Park Service LogoU.S. Department of the InteriorNational Park ServiceNational Park Service
National Park Service:  U.S. Department of the InteriorNational Park Service Arrowhead
Arches National ParkSego Lily
view map
text size:largestlargernormal
printer friendly
Arches National Park
Crescent Milkvetch
Astragalus amphioxys

Astragalus amphioxys var. amphioxys

Family: Fabaceae (A Utah Flora – Leguminosae) - Pea Family

Perennial herbs from a taproot; 0.8” to 1.2' (2 to 35 cm) tall

Leaves: alternate; compound; 0.08” to 0.52” (2 to 13 mm) long; leaflets 0.12” to 0.8” (3 to 20 mm) long; 0.04” to 0.36” (1 to 9 mm) wide

Flowers: rarely flowers the first year; 5 lobed petals (a banner, 2 wings and 2 keels); 5 toothed sepals; bisexual; pink, purple, or rarely white; 10 to numerous stamens, 1 pistil; flowers 0.66” to 1.24” (16.5 to 31 mm) long

Pollinators: other Astragalus species are pollinated by insects (specifically bees, moths and butterflies)

Fruits: legume

Blooms in Arches National Park: January, February, March, April, May, June

Habitat in Arches National Park: desert shrub and pinyon-juniper communities

Location seen: around Visitor Center buildings, park road mile 0 to 2.5, Courthouse towers, Windows, park road mile 9.8, outside Arches National Park on Portal trail

Other: The genus name, “Astragalus”, is the Greek name for “legume”, and may be derived from “astragalos” which means “ankle bone” referring to the shape of the leaves or the pods. The species name, “amphioxys”, is possibly from the Greek “amphi” meaning “both kinds of or double” and "oyxs" meaning “sharp” in reference to the pointed ends of the seedpods.

This family is ranked second to grasses in importance to people because species can fix nitrogen. However, some species, e.g., locoweeds and milkvetches, are poisonous due to selenium abstracted from the soil.

Mule Deer  

Did You Know?
Feeding wildlife can be very detrimental to their health. It can destroy their natural ability to find food and create a dependency on humans. Animals that develop such a dependency often become aggressive toward humans and must be relocated or even killed.

Last Updated: July 19, 2007 at 01:59 EST