Stem stout, much branched, to 2 m; principal lvs twice or thrice pinnately compound, with wholly separate lfls, the uppermost less dissected or even simple; lfls linear to lanceolate, 3-10 cm, sharply and coarsely serrate to nearly entire, the primary lateral veins directed to the sinuses, whence one fork often extends into a tooth; umbels numerous, surpassing the leafy shoot, 5-12 cm wide; fr ovoid to orbicular, 2-4 mm, with prominent, rounded, pale brown ribs separated by darker intervals; 2n=22. Swamps, marshes, and ditches; N.S. and Que. to Alas., s. to Fla., Calif., and Mex. June-Aug. (C. mexicana) We have only the var. maculata.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.

Welsh et al. 1993, Martin and Hutchins 1980

Duration: Perennial Nativity: Native Lifeform: Forb/Herb General: Stout perennial from tuberous base, stems to 2 m tall. Leaves: Alternate, basal and cauline, once to thrice pinnately compound with dentate leaflets, 4-7 opposite pairs of leaflets linear-lanceolate to lanceolate, 3-10 cm long, margins serrate to incised. Flowers: Compound umbels on peduncles 5-15 cm long, bracts of the involucre lacking or with few linear bracts to 1 cm long, 15-26 rays, these 1.5-4 cm long, pedicels 3-10 mm long; calyx teeth about 0.5 mm long, pale green with whitish margins, petals white, stamens white, with depressed-conic stylopodium. Fruits: Ovoid to orbicular, 2-4 mm long, corky, green with prominent ribs. Ecology: Found along streams and rivers, along margins of ponds and lakes, and in wet meadows and marshes from 4,500-8,000 ft (1372-2438 m); flowers June-September. Notes: This plant is highly poisonous, think Socrates. Pay attention to the purple spots near the base of the stem where it meets the ground, this is good for distinguishing this species and Conium maculatum, the invasive hemlock. Ethnobotany: There are some uses for this plant, albeit a poisonous plant. Used as insecticide, for sterility if ingested, ceremonially, to help with broken bones and bruises, and as a poison for hunting. Etymology: Cicuta is the Latin name for hemlock, while maculata means spotted. Synonyms: None Editor: SBuckley, 2010

From Flora of Indiana (1940) by Charles C. Deam

This plant is poisonous and each year in this state there are reports of the death of stock due to eating it. A man in Wells County, mistaking the tuberous roots for sweet anise, ate them and died. Frequent throughout the state in low ground about lakes and ponds, in low woods, and in and along ditches.

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Indiana Coefficient of Conservatism: C = 6

Wetland Indicator Status: OBL

Diagnostic Traits: glabrous perennials with purple-blotched stems; leaves ternately compound, the lanceolate to ovate (greater than 5 mm wide), the lateral veins ending in the sinuses between marginal teetch; umbel ebracteate; petals white; sstyles becoming 1-2 mm; fruits 3-5 mm.