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Heracleum
See list of 3 species in this genus-
1a. Umbel with mostly 50–150 primary branches, up to 50 cm wide; leaflets of principal leaves up to 130 cm long; schizocarp on a pedicel 15–40 mm long, with oil tubes 0.8 mm wide or wider that extend (50–) 65–75% of the way from apex to base of mature fruit
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1b. Umbel with mostly 15–45 primary branches, rarely exceeding 20 cm wide; leaflets of principal leaves 5–30 (–60) cm long; schizocarp on a pedicel 6–20 mm long, with oil tubes up to 0.5 (–0.8) mm wide that extend 50–60 (–70%) of the way from apex to base of mature fruit
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2a. Leaves with 3 ternately arranged, sharply serrate leaflets [Fig. 350]; umbels with 5–10 bracts; larger leaflets 10–30 (–60) cm long; stylopodium not, or only slightly, extending above a deep notch in the mericarp
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2b. Leaves with 3–7 pinnately arranged, often bluntly toothed, leaflets; umbels with fewer than 5 bracts, or lacking bracts altogether; leaflets mostly 5–10 cm long; stylopodium extending above a notch in the mericarp
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Each photo represents one species in this genus.