[The Milk-vetch East of the Cascade Mts.]

Cusick's Milkvetch, Cusick's Milk-vetch

Astragalus cusickii var. cusickii

Astragalus cusickii var. cusickii

The photo above shows the attractive form of Cusick's milkvetch (variety cusickii) as seen along Oregon Highway 3 near the Oregon-Washington Border...................July 7, 2008.

The photo at right shows the inflated pods of Cusick's milk-vetch (var. cusickii) that are slightly mottled or may be totally lacking of mottling. Note that the pedicesl are slightly declined. Photographed from near Brogan Hill Summit,US 26, northern Malheur County, Oregon......June 27, 1999.
Characteristics:

Also known as barren milk-vetch or Packard's milk-vetch, Cusick's milk-vetch is a slender, sparsely leafy perennial, with clustered stems from 10-70 cm tall. Plants range from glabrous to sparsely haired with short, appressed hairs. The slender stems are stiff and ascending to erect. The leaves vary from 3-12 cm in length, with 7-17 narrowly linear, linear-oblong, or linear-elliptic leaflets from 10-25 mm long (See photo below.). Individual leaflets are usually scattered widely on the leaf and have margins that are rolled upwards.

The flower stems typically are longer than the uppermost leaves. The racemes are loosely flowered, with from 2-14 white or creamy-white flowers (often tinged with pinkish-purple) with the corollas from 12-15 mm long. the banner is slightly reflexed away from the keel and measures from 8-15 mm long while the wings are 1-2 mm shorter and the keel from 8-12 mm long. The bell-shaped is 5-6 mm long with broadly triangular teeth. The pods are pendulous and either symmetrically or obliquely obovoid or ellipsoid in shape (See photos). The pods become like inflated bladders as they dry, with varying amounts of reddish mottling on the smooth surfaces. The pods range from 20-48 mm long and 7-16 mm wide.


Varieties of Cusick's Milk-vetch:

variety cusickii: Plants with stems not arising from elongated, running rootstocks. Pods slightly mottled to lacking mottling (See photo at right above.). Leaflets from 5-18 mm long. Found on rocky hillsides, canyon terraces and cliff ledges from 400-900 meters in elevation from southeastern Washington (south of the Snake River) south to the lower Malheur River, Willow Creek and Snake River valley of northern Malheur County and east to Washington County in Idaho.

variety sterilis: Plants with stems arising from elongated, running rootstocks. Pods brightly red-mottled. Leaflets from 2-5 mm long. Found in ashy soils on bluffs, talus slopes and on open hilltops of the Owyhee Desert from Malheur county in southeastern Oregon east into Owyhee County in Idaho.


Habitat:

Cusick's Milk-vetch is found below 4600 feet on rocky hillsides, talus-slopes, and barren hilltops.


Range:

Cusick's Milk-vetch is found from southeastern Washington south through eastern Oregon, and east through the Salmon and Snake River canyons of Idaho.


Close-up sideview of the flower of Cusick's Milkvetch, Cusick's Milk-vetch: Astragalus cusickii var. cusickii - Close-up sideview of the flower of Cusick's Milkvetch, Cusick's Milk-vetch: Astragalus cusickii var. cusickii

Cusick's Milkvetch, Cusick's Milk-vetch: Astragalus cusickii var. cusickii - Cusick's Milkvetch, Cusick's Milk-vetch: Astragalus cusickii var. cusickii - Partially inflated pods of Cusick's Milkvetch, Cusick's Milk-vetch: Astragalus cusickii var. cusickii

Cusick's Milkvetch, Cusick's Milk-vetch: Astragalus cusickii var. cusickii - Cusick's Milkvetch, Cusick's Milk-vetch: Astragalus cusickii var. cusickii

Upper stem leaves and inflorescence of Cusick's Milkvetch, Cusick's Milk-vetch: Astragalus cusickii var. cusickii

Additional close-up photos of Cusick's milkvetch as seen in Asotin County, Washington.................May 24, 2010. Note the photo showing partially inflated pods compared with those that are nearly inflated, both from this location as well as other sites.

Inflated pods of Astragalus cusickii var. cusickii ----- Pinnately compound leaf of Astragalus cusickii var. cusickii

The 2 photos above show close-ups of the attractive, inflated pods and pinnately compound leaf of Cusick's milkvetch (variety cusickii) as seen along Oregon Highway 3 near the Oregon-Washington Border...................July 7, 2008. Click each photo to see enlarged views (3x).

Astragalus cusickii var. cusickii ----- Astragalus cusickii var. cusickii

The 2 photos above show Cusick's milkvetch (variety cusickii) as seen along Oregon Highway 3 near the Oregon-Washington Border...................July 7, 2008. Click each photo to see enlarged views (4x).

Astragalus cusickii v. cusickii

Cusick's milk-vetch (variety cusickii) from near Brogan Hill Summit,US 26, northern Malheur County, Oregon......June 27, 1999.

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Photos above of the pod (notice minor reddish speckling on surface of pod) and leaves with long, linear leaflets of Cusick's milk-vetch (variety cusickii).

Paul Slichter