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Cowparsnip (Heracleum lanatum)

• Family: Carrot (Apiaceae)
• Flowering: May-July.
• Field Marks: This species is distinguished from all other white-flowered members of the family by its stout growth form and its huge, hairy, palmately lobed leaves. The seeds are marked with 4 vertical purple lines.
• Habitat: Along streams, lowland woods.
• Habit: Coarse biennial herb with a taproot.
• Stems: Erect, branched, rough-hairy, hollow, up to 8 feet tall.
• Leaves: Pinnately divided or palmately cleft, alternate, ovate, rough-hairy, coarsely toothed, up to 1 1/2 feet long, with a broad wing at the base of the leaf stalk.
• Flowers: Many borne in large, many-rayed umbels; each umbel subtended by very narrow bracts up to 1 inch long; some of the flowers with stamens only.
• Sepals: 5, green, minute.
• Petals: 5, white, free from each other, not all the same size, up to 1/3 inch long.
• Stamens: 5.
• Pistils: Ovary inferior.
• Fruits: Flat, obovate, smooth or nearly so, with 4 conspicuous vertical purple lines.