Astragalus canadensis L.

Astragalus canadensis plant

Family - Fabaceae

Stems - Multiple from base, erect, divaricately branching, reddish in strong sun, herbaceous, fistulose, from rhizomes, appressed pubescent. Hairs of stem running parallel to axis of stem, attached in the middle (=malpighaceous).

Astragalus canadensis stem

Leaves - Alternate, odd pinnate, stipulate. Stipules attenuate, to 5mm long, pubescent.  Leaflets opposite, 13-20 pairs per leaf, mucronate, entire, elliptic to lance-oblong, appressed bifurcate pubescent above and below (less so above), gradually decreasing in size towards tip of leaf. The larger leaflets 1.3cm wide, 3cm long. Petiolules to 1.5mm long.

Astragalus canadensis leaf

Inflorescence - Axillary racemes to +/-15cm long(high), 30-70 flowered. Peduncle carinate, pubescent. Pedicels 1.1mm long, each subtended by a linear-attenuate bract to 6mm long.

Astragalus canadensis inflorescence

Flowers - Corolla papilionaceous, creamy white to greenish white or with a tinge of lilac, to 2cm long. Standard 6mm broad, notched at apex, 1.4cm long. Keel petals with purplish spots at apex. Stamens diadelphous. Anthers yellow, .5mm long. Filaments glabrous. Ovary green, 5mm long, terete, very sparse pubescent. Style white, to +7mm long, glabrous, upcurved. Calyx tube less than half the length of the corolla, pubescent, whitish-green, 5-lobed. Lobes to 2mm long, acute. Fruits inflated, to 1.1cm long, beaked with persistent style, typically glabrous, 2-valved, with +/-10 seeds.

Astragalus canadensis flowersFlowers.

Astragalus canadensis calyxCalyx close-up.

Astragalus canadensis plantFruit.

Flowering - May - August.

Habitat - Thickets, wet lowlands, pastures, prairies, upland woods, waste ground.

Origin - Native to U.S.

Other info. - This species can be found throughout Missouri and is absent only from the extreme southeastern portion of the state. The plant is easy to identify while in flower but vegetatively it can be mistaken for many other plants. It is the most common Astragalus in Missouri.
This species grows about as wide as tall and would make an excellent specimen garden plant.

Photographs taken at the Kansas City Zoo, 7-10-00, and in the Ozark Scenic Riverways, Shannon County, MO., 7-6-03.


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