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Beaver Poison

Cicuta maculata (sih-KYOO-tah mak-yoo-LAY-tah)

Family: Apiaceae Native Herbaceous

Water Hemlock is a perennial herb with short tuberous roots and purple-striped or mottled, hollow stems with cross-partitions at the nodes and many of these at the base of the stem. Its leaves are alternate, clasp the stem, are 2-3 pinnately divided, and have leaflets with the veins ending in the notch between the teeth. These veins distinguish the Water Hemlock from other members of the Carrot family. In its first year, it will be in the form of a low-growing rosette. Maturing in the second year, it will develop a tall stalk, growing to up to 8'. The tiny flowers are small, white, and form in umbrella-like clusters. They bloom from spring to fall, attracting a variety of bee, wasp and butterfly species. It is a host plant for the Black swallowtail butterfly ( Papilio polyxenes ) . Although all parts of the plant are highly toxic, however, water birds do eat the fruits without effect. Site: Wet meadows, thickets, fresh water swamps, roadside ditches, floodplains Found in: Forest or natural area in wet areas, pond, stream, or ditch banks. Insects, Diseases, and Other Plant Problems: All parts of the plant are poisonous, with the roots more poisonous than the other parts.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 66 attributes.

How it fits the guild

Guild layer 4 - Herbaceous Optimal soil pH Acid (<6.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Often confused with Daucus carota

Full plant profile

Growing Conditions
Plant type
Herbaceous Perennial; Native Plant; Poisonous; Wildflower
Life cycle
Biennial; Perennial
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
High Organic Matter; Loam (Silt); Sand
Soil pH
Acid (<6.0); Neutral (6.0-8.0)
Soil drainage
Moist | Occasionally Wet
Available space
12 inches-3 feet; 3 feet-6 feet
NC region
Coastal; Mountains; Piedmont
Growth rate
Rapid
Maintenance
Medium
Canopy layer
4 - Herbaceous
Form & Appearance
Habit / form
Erect
Texture
Medium
Leaf color
Green
Leaf type
Compound (Pinnately , Bipinnately, Palmately)
Leaf arrangement
Alternate
Leaf shape
Elliptical; Lanceolate
Leaf margin
Serrate
Leaf feel
Smooth
Leaf size
3-6 inches long, 1-3 inches wide
Hairs present
No
Leaf detail
The lower compound leaves are up to 1 ft., doubly divided with veins ending at notches between the teeth. They are smooth, erect highly branched stem. The upper leaves are somewhat smaller than the lower leaves. Individual leaflets are up to 4" long and 1 1/4" wide.
Flower color
White
Flower value
Fragrant
Flower form
Umbel
Flower shape
Star
Flower size
< 1 inch
Flower detail
Compound umbels can form on the upper portion of the stems. Reaching up to 6", each umbels can have 10-20 dome shaped umbellets. The individual umbellets can have up to 15 flowers. The tiny, 1/8" flowers may have a slight fragrance.
Bloom time
Summer
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Each fruit contains 2 seeds. They do not split open when ripe.
Stem color
Green; Pink; Purple/Lavender
Stem detail
Purple-striped or mottled, hollow stems with cross-partitions at the nodes and many of these at the base of the stem. May have longitudinal veins.
Wildlife & Ecology
Native status
Native
Origin
North America
Wildlife value
The nectar from the flowers attracts a variety of bees, wasps, flies, moths, butterflies, and a variety of other insects that have short mouth parts. It is a host plant for the Black swallowtail (Papilio polyxenes) butterfly. The fruits that are produced are eaten by water birds.
Attracts
Bees; Butterflies; Moths; Pollinators; Specialized Bees
Play value
Attracts Pollinators; Wildlife Larval Host
Food & Medicine

Edibility

All parts of the plant are toxic when eaten.

Uses (ethnobotany)

Naturalized areas

Landscape Use
Landscape location
Naturalized Area; Woodland
Landscape theme
Butterfly Garden; Native Garden; Pollinator Garden; Rain Garden; Water Garden
Garden tags
#NC native #problem for cats #problem for horses #problem for dogs #poisonous #poisonous leaves #aphids #wasps #fly friendly #butterfly garden #native perennial #naturalizes #butterfly caterpillar host #self-seeding #butterfly friendly #pollinator plant #herbaceous #herbaceous perennial #pollinator garden #naturalized area #host plant #bee friendly #NC Native Pollinator Plant
Problems & Resistance
Insect problems
Aphids Found on Flowers and Foliage; Aphids on Ornamental Landscape Plants
Problems
Problem for Cats; Problem for Dogs; Problem for Horses
Resistant to
Wet Soil
Propagation
Seed
Poison severity
High
Poison parts
Bark; Flowers; Fruits; Leaves; Roots; Seeds; Stems
Poison symptoms
HIGHLY TOXIC, MAY BE FATAL IF EATEN! Muscle spasms, dilated pupils, dizziness, diarrhea, stomach pain, convulsions. Seizures, tremors, fever, bloat, respiratory depression
Toxic principle
Cicutoxin and cicutol
Contact dermatitis
No
Toxicity summary
High severity poison; parts: Bark; Flowers; Fruits; Leaves; Roots; Seeds; Stems

Planted at Hunnicutt

Nobody’s planted this one yet.