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Aquatic and Wetland Vascular Plants of the Northern Great Plains

34. Apiaceae, the Parsley Family

2. Cicuta L. -- Water hemlock

2. Cicuta maculata L. -- Common water hemlock


Stout biennial or perennial from sterile offshoots produced from the dying main plant, 5-20 dm tall; stems solitary or few together from a tuberous-thickened and chambered base, conspicuously hollow above the base, the roots partly tuberous also. Leaves basal and cauline, the basal leaves larger and longer-petioled than cauline leaves, the blades oblong to ovate in general outline, mostly 8-25(35) cm long, 5-15(20) cm wide; leaflets linear-lanceolate to ovate-lanceolate, mostly 3-10 cm long, 5-35 mm wide, serrate. Umbels several to many, 6-12 cm wide in fruit, on stout peduncles 5-15 cm long; rays 2-6 cm long; bracts none or few to several, narrow; umbellets 1-2 cm wide at maturity, the pedicels 3-10 mm long; bractlets ovate-lanceolate to linear, scarious-margined, 2-15 mm long. Fruits rotund-ovate to orbicular, 2-4.5 mm long, glabrous, constricted or not constricted at the commissure, with prominent dorsal and lateral corky ribs. Jul--Sep. Wet meadows, marshes, shores, stream banks, springs and other wet places; common; (Que. to AK, s to FL, TX, NM, AZ, CA and into n Mex.). C. douglasii (DC.) Coult. & Rose.

Two varieties of C. maculata occur in our region. C. maculata var. angustifolia Hook. has styles usually less than 1 mm long; fruits constricted at the commissure, the lateral ribs (those bordering the commissure) separated by the groove of the constriction, about equaling the dorsal ribs in width; principal stem leaflets more than 5X longer than wide. Var. angustifolia is the prevalent form in the w part of our region. This variety has been recognized as a distinct species by many authors who have referred to it as C. douglasii (DC.) Coult. & Rose.

C. maculata var. maculata differs in having styles usually more than 1 mm long; fruits not constricted at the commissure, the lateral ribs contiguous, each considerably broader than the dorsal ribs; principal stem leaflets less than 5X longer than wide. This variety is most common in the e part.
GIF- Species Photo/Drawing

Cicuta maculata, lower stem with tuberous roots and terminal flowering portion.
GIF- Distribution Map

Map key


Previous Section -- Cicuta bulbifera L. -- Bulbous water hemlock
Return to Family -- Apiaceae - The Parsley Family
Next Section -- Sium suave Walt.

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