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Astragalus allochrous - halfmoon milkvetch

Scientific Family
Fabaceae
Plant type
Forbs and Subshrubs
Origin
Native
Lifecycle
Perennial
Height
To 20 inches
Riparian
No

Relatively small species, producing short, reddish leaf stems (petioles) and pinnately compound leaves.

Short-lived perennial having no visible stem; leaves compound, leaflets narrow to somewhat broadened; short stiff hairs on both sides; flowers purple in many-flowered racemes; pods inflated.

Habitat

Sandy flats, open areas.

Plant Community
Desert Scrub
Disturbed Areas
Grasslands
Interior Chaparral
Pinyon Juniper Woodlands
Low elevation
100
High elevation
6000

Flower Characteristics

Flowers form in racemes of 5 to 10 or more. Petals are usually purple (less often white), the banner having white streaks at the center, while the flower bracts are initially green, becoming red-purple. The banner petal is curved back at about 45 degrees.

Flower color
White to purple
Flower shape
Irregular
Tubular
Yes
First bloom month
March
Last bloom month
May
Flower clusters
Elongated

Leaf and Stem Characteristics

Leaves and stems are covered by short hairs that press against the surface. Leaflet margins are often red-purple, while the leaflets are about 1/3 inch long and tend to fold up along the axis. The tips of the leaflets are either flat or shallowly notched.

Leaf type
Compound
Leaf color
Green to reddish-purple
Leaf shape
Pinnatifid
Leaf margin
Smooth
Leaf attachment
Opposite
Leaves clasp
No
Leaf hairs
Leaves & stems
Spines
No

Fruit and Seed Characteristics

The common name, halfmoon milkvetch, refers to the shape of the seed pods, which are papery and inflated. They are initially greenish, later red.

Fruit type
Pod
Fruit color
Green to red