Astragalus species

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Scientific Name Astragalus cicer USDA PLANTS Symbol ASCI4
Common Name Chickpea Milkvetch, Cicer Milkvetch ITIS Taxonomic Serial No. 25464
Family Fabaceae (Pea) SEINet
Reference
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Description Life zones and habitat: Foothills to subalpine (5600 to 11000 ft); open areas, pastures, shrublands, aspen woodlands. Introduced species from Europe; found in western and northern US.
Plant: Erect or leaning perennial, a foot or more high, upright when young and becoming decumbent and trailing.
Leaves: Pinnately-compound leaves 4 to 8 inches long, each with 10 to 13 pairs of deep green oblong leaflets 3/4 to 2 inches long, with pointed tips and somewhat hairy undersides.
Inflorescence: Clusters of 15 to 60 pale yellow to white pea-like flowers in a compact raceme; light green calyx is covered by short, light or dark hairs.
Bloom Period: June to August.
Fruit: Pods green or reddish, turning straw-colored to black, silvery hairs; ovoid to ellipsoid to linear-oblanceolate 3/8 to 1/2+ inch long.
Reference: "Flora of Colorado" by Jennifer Ackerfield, American Southwest, and USDA-NRCS Plant Guide.
BONAP Distribution Map

Colorado Status:
Introduced
Scientific Name Astragalus kentrophyta USDA PLANTS Symbol ASKE
Common Name Spiny Milkvetch ITIS Taxonomic Serial No. 25553
Family Fabaceae (Pea) SEINet
Reference
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Description Life zones and habitat: Plains to subalpine (4000 to 10800 ft.); sandy or rocky soils in open areas.
Plant: Low-growing perennial with prostrate stems a few inches high forming mats up to 16 inches across.
Leaves: Odd pinnately-compound leaves up to 1-inch long, each with 3 to 7 spine-tipped linear-elliptic or linear-oblanceolate leaflets up to 2/3-inch long; surfaces flat or curled inward with appressed or dolobriform hairs.
Inflorescence: Short racemes in the leaf axils, each with 1 to 3 small pea-like flowers barely rising above the leaflets; white to yellowish-white or pink-purplish corolla and banner 1/4 to 1/2-inch long; calyx ~1/4-inch long and pubescent-hairy.
Bloom Period: May to August.
Fruit: Small compressed-ovoid pods less than 1/3-inch long, green, becoming straw colored.
Reference: "Flora of Colorado" by Jennifer Ackerfield, American Southwest, Montana Field Guide and SEINet.
BONAP Distribution Map

Colorado Status:
Native
Scientific Name Astragalus pattersonii USDA PLANTS Symbol ASPA14
Common Name Patterson Milkvetch ITIS Taxonomic Serial No. 25625
Family Fabaceae (Pea) SEINet
Reference
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Description Life zones and habitat: Semi-desert to foothills (5000 to 8500 ft); dry clay or shaley soils on hillsides, flats.
Plant: Erect clump-forming perennial, 9 to 28 inches high; arching red stems.
Leaves: Pinnately-compound leaves with up to 13 pairs of deep green elliptic to oblong leaflets 0.2 to 1.2 inches long, with pointed tips and smooth upper surfaces, somewhat hairy beneath.
Inflorescence: Clusters of white pea-like flowers in a compact raceme; calyx tubes with conspicuous fringe-like lobes and tiny black hairs; blossoms becoming yellowish with age.
Bloom Period: May to July.
Fruit: Smooth, green or brownish pods, ellipsoid shape 5/8 to 1 inch long, pointed tips.
Reference: "Flora of Colorado" by Jennifer Ackerfield and SW Colorado Wildflowers.
BONAP Distribution Map

Colorado Status:
Native
Scientific Name Astragalus scopulorum USDA PLANTS Symbol ASSC7
Common Name Rocky Mountain Milkvetch ITIS Taxonomic Serial No. 25670
Family Fabaceae (Pea) SEINet
Reference
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Description Life zones and habitat: Foothills to subalpine (6300 to 11000 ft); sunny areas, dry slopes, among sagebrush, conifer woodlands and aspen groves.
Plant: Erect or leaning perennial, light-red stems 6 to 18 inches tall.
Leaves: Pinnately-compound leaves each with 15 to 29 green oval-oblong to linear-elliptic or oblanceolate leaflets with pointed tips, 1/4 to 3/4-inch long and somewhat hairy undersides.
Inflorescence: Raceme of 10 to 22 white to pale yellow pea-like flowers; light green calyx is covered by short, light or dark hairs.
Bloom Period: May to July.
Fruit: Green or greenish brown, purple-speckled, smooth pods linear-oblong to linear-oblanceolate 1 to 1-3/8 inches long.
References: "Flora of Colorado" by Jennifer Ackerfield, Wildflowers of the Rocky Mountain Region by Denver Botanical Garden and SW Colorado Wildflowers.
BONAP Distribution Map

Colorado Status:
Native

© Tom Lebsack 2021