Host an Event Volunteer Join Tickets

Support the plant database you love!

Share

Plant Database

Search for native plants by scientific name, common name or family. If you are not sure what you are looking for, try the Combination Search or our Recommended Species lists.

Enter a Plant Name:
Or you can choose a plant family:

Astragalus argophyllus var. argophyllus

Astragalus argophyllus Nutt. var. argophyllus

Silverleaf Milkvetch

Fabaceae (Pea family)

Synonym(s): Xylophacos argophyllus

USDA Symbol: ASARA

USDA Native Status: L48 (N)

"Root and caudex stout, tough, heavy; hairs of the herbage either all appressed or mostly narrowly ascending, straight or nearly so, up to (0.75) 1-1.65 mm. long; stems almost 0 up to 1 (1.5) dm. long." (bibref: 1814).

"The silver-leaved milk-vetch is one of the few astragali of the intermountain region and the only one with large, purple flowers and silvery-silky leaflets that is confined to moist heavy soils, where it is subject to competition with sod-forming grasses, sedges, and other relatively rank herbaceous growth. The plants spring into flower with the year’s first warm weather, along with Carex Douglasii and Dodecatheon radicatum, and at anthesis form handsome ground-hugging mats or low tufts of silvery foliage seated on an extremely tough, woody root. The root and caudex, difficult to collect, are seen seldom in herbarium specimens. As the season advances and the surrounding turf grows up into the hay of summer, the piants are hidden from ready view and the green, fleshy, humistrate ovaries ripen slowly, in concealment, into the straw-colored or ultimately blackish, readily deciduous pods. The leaf-rachis in A. a. var. argophyllus is comparatively slender and flaccid, the leaflets tending to be small, distant, and diamond-shaped. Dried material does little justice to the brilliance of the fresh flower which dries out rapidly from a lively pink-purple to a dull slate-blue." (bibref: 1814).

 

From the Image Gallery

No images of this plant

Plant Characteristics

Duration: Perennial
Habit: Herb
Leaf Arrangement: Alternate
Fruit Type: Legume
Size Notes: "Stems almost 0 up to 1 (1.5) dm. lon." (bibref: 1814).
Leaf: "Stipules submembranous becoming papery, often brownish when old, 2-8 (10) mm. long, the lowest (often dorsally glabrate) and sometimes all ovate or broadly lanceolate, the upper ones commonly longer and narrower, decurrent-amplexicaul around half to the whole stem's circumference, but the margins, even when in contact, not united; leaves 1.5-12 (15) cm. long, those subtending the peduncles sometimes much longer than the rest, all slender- petioled, with 7-21 rhombic-elliptic, oval-oblanceolate, or obovate-cuneate, acute or obtuse, distant or crowded, flat or loosely folded leaflets 2-15 mm. long." (bibref: 1814).
Flower: "Peduncles almost 0 to 9 cm. long, usually much and always a little shorter than the leaf, incurved-ascending at anthesis, arcuately reclinate or prostrate in fruit; bracts membranous or broadly membranous-margined, ovate or lanceolate, 1.8-6.5 mm. long; pedicels ascending or a trifle arched outward, at anthesis slender, 1.2-3.2 mm. long, in fruit a little thickened, 1.8-3.8 mm. long; bracteoles commonly 0, exceptionally present and up to 2.5 mm. long; calyx 12.4-16.8 mm. long, pubescent like the herbage with white and often some or nearly all black hairs, the somewhat oblique disc 1-2.5 mm. deep, the cylindric, pallid or purplish the tube (9.4) 10-11.8 mm. long, 3.4-4.6 mm. in diameter, the subulate or linear-subulate teeth 2.4-5 (5.8) mm. long, the whole becoming papery, ruptured, marcescent; petals either bright pink-purple (drying bluish), or tinged with lilac or dull purple; banner oblanceolate, broadly rhombic-oblanceolate, or spatulate, notched, 15-24 mm. long; wings 20.6-23.8 mm. long, the lance-oblong, obtuse blades rather abruptly narrowed and usually a little incurved in the distal third; keel (17.3) 17.6-20.3 mm. long, the half- obovate or lunately elliptic blades 9.2-12.2 mm. long, 2.1-3.5 mm. wide, gently incurved through 80-90 (95) degrees to the blunt apex; anthers 0.45-0.85 mm. long." (bibref: 1814).
Fruit: "Pod ascending (humistrate), varying from plumply ovoid-acuminate to narrowly lance-elliptic in profile, 1.5-2.5 cm. long, 7-12 mm. in diameter, either straight proximally and incurved into the deltoid or triangular-acuminate, laterally compressed beak, or gently incurved (through up to 1/2-circle) its whole length, obcompressed and dorsally flattened or very shallowly and widely sulcate in the lower ?, the ventral suture thick and prominent but sometimes depressed and lying in a double groove, the more or less fleshy, green valves becoming brownish, stiffly leathery or woody, faintly to quite strongly rugulose-reticulate and sometimes also wrinkled lengthwise on the ventral side, strigulose-pilosulous with straight, appressed or subappressed hairs up to (0.35) 0.5-1 mm. long, not inflexed; dehiscence apical, the ventral suture finally splitting but not separating; ovules 25-43; seeds brown, smooth or sparsely pitted, dull, 1.7-3 mm. long." (bibref: 1814).

Bloom Information

Bloom Color: Pink , Blue , Purple , Violet
Bloom Time: May , Jun , Jul
Bloom Notes: "Petals either bright pink-purple (drying bluish), or tinged with lilac or dull purple." (bibref: 1814).

Distribution

USA: CA , ID , MT , NV , UT , WY
Native Distribution: "Scattered but locally abundant, central and northwestern Nevada north and eastward across the Snake River Plains to the upper forks of the Salmon River in Idaho, extreme southwestern Montana, the upper Wind River, Wyoming, and the San Pitch River in central Utah." (bibref: 1814).
Native Habitat: "Alkaline and saline meadows, moist at least in spring, stream banks and lake shores, in stiff alluvial clays and loams, sometimes in damp crevices about hot springs, 4500—7650 feet." (bibref: 1814).

Bibliography

Bibref 1814 - Atlas of North American Astragalus Volume 2 (1964) Barneby, Rupert C.

Search More Titles in Bibliography

Additional resources

USDA: Find Astragalus argophyllus var. argophyllus in USDA Plants
FNA: Find Astragalus argophyllus var. argophyllus in the Flora of North America (if available)
Google: Search Google for Astragalus argophyllus var. argophyllus

Metadata

Record Modified: 2020-12-07
Research By: Joseph A. Marcus

Go back