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Astragalus
See list of 6 species in this genus-
1a. Plants annual; legume usually curved to twisted, often forming a complete circle of less than 10 mm diameter
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1b. Plants perennial; legume straight to somewhat curved, but not twisted
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2a. Corollas ochroleucous in life; legume bilocular, usually glabrous
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3a. Pubescence of herbage basifixed; legume 30–40 mm long, trigonous in cross-section; principal leaves with 9–13 leaflets
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3b. Pubescence of herbage mesifixed; legume 10–20 mm long, terete in cross-section; principal leaves with 13–35 leaflets
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2b. Corollas white to light purple, blue-purple, or purple in life; legume unilocular (note: one of the sutures may be intruded but does not connect to form 2 separate chambers in the fruit), usually pubescent
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4a. Principal leaves with 15–25 leaflets [Fig. 631]; stems from a subterranean, branched caudex, mat-forming; keel petals not or only slightly shorter than the banner petal; upper suture of fruit prominently sulcate
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4b. Principal leaves with 7–15 (–17) leaflets; stems from a surficial crown of a taproot, clustered but not forming mats; keel petals markedly shorter than the banner petal; upper suture of fruit scarcely sulcate
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5a. Legume (5–) 8–11 (–13) mm long, ± sessile; flowers 6–9 mm long
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5b. Legume 13–25 mm long, on a stipe 2–5 mm long; flowers (7–) 10–12 mm long
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Show photos of:
Each photo represents one species in this genus.