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

Canada Milk-vetch

Astragalus canadensis var. mortonii

The photo above shows a close-up of the inflorescence of Canada milk-vetch. Note the whitish-yellow corollas and assymetrical calyx tube covered with dark hairs. Photographed along the highway to Chewelah Peak in the Colville N.F....................June 23, 2006.

Characteristics:

Canada milk-vetch is a robust perennial wildflower with ascending to erect stems from 15-100 cm high arising singly or several together from spreading rhizomes. The leaves and stems are covered with short, fine, appressed hairs or may be green and glabrous. The pinnately compound leaves are 5-35 cm long with 13-35 leaflets measuring 10-45 mm long and broadly lanceolate, oblong, ovate or elliptic in outline.

The erect flower stems are 4-22 cm long. The densely flowered racemes elongate to 2.5-16 cm long and 2.5-3.5 cm wide when mature and bear up to 150 flowers. The calyx is bell-shaped but assymetrical at its base (See photo above.) and measures 4.5-8.5 mm long with awl-shaped to triangular teeth from 1-4 mm long. It is covered with whitish to black hairs that are appressed to the calyx tube or spreading. The petals are greenish-white or whitish-yellow or may be purple-tinged. The moderately recurved banner is 12-17.5 mm long while the wings are 10-15 mm long and the obtuse keel is 10-13.5 mm long. The erect, sessile pod is oblong-cylindric or ellipsoid in shape with an abruptly rounded base. The pods measure 8-20 mm long and 3-5 mm wide and are covered with minute, appressed hairs or are glabrous.

The photo above shows a close-up of the pinnately compound leaf of Canada milk-vetch with its ovate-lanceolate leaflets. Photographed along the highway up to Chewelah Peak in the Colville N.F...................June 23, 2006.

Habitat:

Canada milk-vetch may be found in vernally to permanently moist places along streams, in prairie or in woodland.


Range:

Canada milk-vetch may be found from northern British Columbia south to central California, central Nevada and southwestern Utah. It is found eastward to James Bay, Ontario and New England and south to South Carolina. It is found south through the Rocky Mts. to north-central New Mexico and eastward to southeastern Texas.


The photo above shows a close-up of a flower of Canada milk-vetch as seen on the highway to Chewelah Peak in the Colville N.F....................June 23, 2006.

The photo above shows the inflorescence of Canada milk-vetch atop its long, stout flower stem. Photographed near Chewelah Peak in the Colville N.F....................June 23, 2006.

The photo above shows a close-up of the pinnately compound leaf of Canada milk-vetch with its ovate-lanceolate leaflets. Photographed along the Hurricane Creek Trail, Eagle Cap Wilderness...................June 26, 2004.

The photo above shows a close-up of the flower of Canada milk-vetch. Note the whitish-yellow corolla and assymetrical calyx tube covered with dark hairs. Photographed along the Hurricane Creek Trail, Eagle Cap Wilderness...................June 26, 2004.

Paul Slichter