Water Hemlock- Cicuta maculata
Other names include: Spotted Water Hemlock, Water Hemlock,
Common Water Hemlock, Spotted Cowbane, Musquash Root
Leaves alternate, compound, twice or thrice divided,
with petioles that partially sheath the stem. Uppermost leaves not dissected.
Oblong to ovate in general outline, these compound leaves run 3"-10"
long and 2"-6" wide. Basal leaves larger and with longer petioles
than cauline leaves. Leaflets linear to broadly lanceolate,
pointed at the tip, rounded or tapering to the base, mostly 1"-4"
long, ¼"-1¼" wide, hairy, with regularly pointed
and notched edges. Leaflet veins extend into or near the notches of the
leaf rather than in the points.
Stems solitary or few together from a tuberous-thickened
and chambered base, conspicuously hollow above the base. Erect, branched,
each about 2" long. hairy, up to 7' tall. Often has a purple striped
or mottled stem base. glabrous, hollow stems Stems are smooth, branching,
swollen at the base, purple-striped or mottled, and hollow except for
partitions at the junction of the root and stem. with cross-partitions
at the nodes and many of these at the base of the stem
A yellow, oily, highly toxic liquid smelling like parsnips exudes from
cut stems and roots.
Roots partly tuberous, in dahlia-like clusters of 2 to
8 fleshy roots, each about 2" long, with a scent of parsnip.
Flowers white, many; in compound, flat-topped, umbrella-like
clusters at ends of stems and branches.
Sepals 5, green, triangular.
Petals 5, free, white, about 1/10" long.
Ovary inferior (below flower)
Fruit small, dry, nearly spherical, smooth but with prominent
corky ribs; up to ¼" long. Ripening July-September.
Poison Hemlock (Conium
maculatum) is a similar species and a highly toxic
exotic which has become naturalised through much of the eastern US. The
difference between Cicuta maculata and Conium maculatum
is that Conium's leaves are heavily dissected and fernlike, as
opposed to the lanceolate leaflets with sharply-toothed edges of Cicuta
Links to more information
Website, video, and graphics by Rob Nelson
For more information on this plant or management please contact US Army Corp of Engineers
Western Water Hemlock Video
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