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Allium
See list of 7 species in this genusReference: McNeal and Jacobsen (2002).
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1a. Leaves flat, (15–) 20–80 mm wide, produced in early season and soon withering, usually not present during anthesis; capsule prominently 3-lobed
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1b. Leaves flat or terete, 1–20 mm wide, not early withering, present during anthesis; capsule only slightly lobed or not produced
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2a. Umbels composed entirely of flowers, without bulbils
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3a. Pedicels 10–50 mm long, longer than the flowers; scapes 3–20 mm in diameter; bulbs 3–10 cm in diameter; flowers 3–7 mm long; leaf blades semicircular in cross-section, 3–20 mm wide
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3b. Pedicels 2–6 mm long, shorter than to nearly equaling the flowers; scapes 3–5 mm in diameter; bulbs 1.5–2 cm in diameter; flowers 8–12 mm long; leaf blades terete in cross-section, 2–7 mm wide
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2b. Umbels with most or all of the flowers replaced by bulbils
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4a. Bulbs covered with an outer layer of fibrous reticulum [Fig. 60]; leaf-bearing nodes confined to the basal ¼ of scape; inflorescence subtended by 3 or 4 spathiform bracts (note: the bracts are often caducous, so fewer may be present at time of observation)
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4b. Bulbs covered with a membranaceous-scaly outer layer, fibers (if present) not forming a reticulum; leaf-bearing nodes extending to midpoint of scape or higher; inflorescence subtended by 1 or 2 spathiform bracts
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5a. Umbel subtended by 2 persistent, spathiform bracts; flowers 6–8 mm long, on pedicels 15–60 mm long
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5b. Umbel subtended by a solitary, caducous, spathiform bract; flowers 3–5 mm long, on pedicels 10–20 mm long
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6a. Leaf blade hollow in the basal half, terete, 2–4 mm in diameter; bulbs 1–2 cm in diameter
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6b. Leaf blade solid, flat, 5–20 mm wide; bulbs (1.5–) 3–8 cm in diameter
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Each photo represents one species in this genus.