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Poisonous Plant Guide

All Plants


Actaea rubra

These plants grow at higher elevations (8000 feet) in cool, wet places. Grows 3 or 4 feet tall, has a thick stem and thick underground root, large featherlike leaves with a hairy underside. Poisonous parts: all parts, especially root stock and sap.

More About Baneberry


Solanum Dulcamara

Vine-like plant that may grow as high as 6 feet.  Commonly mistaken for Deadly Nightshade.

More About Bittersweet Nightshade

CALLA LILY (Houseplant)

Zantedeschia species

Leaves shaped like arrow heads that may grow to 18 inches long and 10 inches wide. Leaves are glossy green. Stems are longer than the actual leaves. Spathe-shaped white flowers. Berry is not often seen.

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CASTOR BEAN (Cultivated)

Ricinus communis

Usually grown as an annual. May grow six to 15 feet tall. Leaves alternate and may be up to three feet in diameter. Leaves are lobed and have five to 11 points.

More About Castor Bean

COTONEASTER (Cultivated)

Cotoneaster species

May be ground cover to small upright shrub to very tall graceful shrubs (25 feet). Flowers are white or pinkish and bloom in Spring. They resemble tiny single roses. Berries may be red or orange-red.

More About Cottoneaster

DAFFODIL (Cultivated)

Narcissus species

Common garden plant grown from bulbs usually with straight, flat leaves and white or yellow flowers.

More About Daffodil


Zigadenus species

Perennial herb with narrow, grass-like leaves. Yellow or whitish-green flowers form at top of central stalk. Bulbs often mistaken for onion but lack the characteristic onion odor.

More About Death Camus


Euphorbia myrsinites

Grows wild in foothill areas in northeastern Utah, also cultivated in rock gardens. Blue-green diamond-shaped fleshy leaves in close spiral arrangement, end with a tooth-like tip.

More About Donkey's Tail/ Creeping Spurge/ Myrtle Spurge

DUMB CANE (Houseplant)

Dieffenbachia species

House plant that has large leaves up to 20 inches. The plant may reach 2 feet in width. It is generally taller than it is wide. Leaves are dark green to yellow green with variegations in white or pale cream.

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EASTER LILY (Houseplant)

Lilium longiflorum

Leaves are shiny, dark-green and lance shaped. Flowers are white and trumpet-like.

More About Easter Lily


Veratrum species

Grows in damp areas on meadows and hillsides at high elevations. It emerges as soon as snow melts in the spring and reaches a height of 1.5 to 2 meters. Leaves may measure 20 to 30 cm long and 7 to 15 cm broad. Cream-colored flowers grow in clusters at the top of a single unbranched stalk that resembles corn.

More About False Hellebore

FIRETHORN (Cultivated)

Pyracantha species

Habit ranges from upright to sprawling. Glossy green oval shaped leaves. Has needle-like thorns. Planted as shrubs or ground covers in full sun.

More About Firethorn

FOXGLOVE (Cultivated)

Digitalis purpurea

Cultivated in gardens throughout the United States. Grows up to 4 feet tall. Leaves are grayish-green in color and are wooly on their underside.

More About Foxglove

IRIS (Cultivated)

Iris species

Sword or grass-like leaves with showy flowers that bloom in spring or early summer. They grow from bulbs or rhizomes, 1 to 2 feet tall.

More About Iris


Datura Wrightii

Can grow up to 5 feet tall. Stems and leaves are velvety green in color. Flowers are snow-white in color and bloom in the summer. They open in the evening and fade during the day. 

More About Jimson Weed


Convallaria majalis

Naturalized in gardens, prefers partial shade. Ground cover, 6-8 inches high, forms colonies. Broad, glossy green elliptical leaves.

More About Lily of the Valley

LUPINE/BLUE BONNET (Native and Cultivated)

Lupinus argenteus

Grows from lower elevations up to 10000 feet in elevation. Approximately 20 inches tall. Compound leaves, with 6-9 lance-shaped leaflets, with a silvery covering. All parts, especially ripe seeds, are potentially toxic.

More About Lupine/ Blue Bonnet

OLEANDER (Cultivated)

Nerium oleander

Evergreen shrub up to 20 feet tall. Leaves are leathery, dark green, long, and narrow to ten inches with pointed tip.

More About Oleander

OREGON GRAPE (Native and Cultivated)

Mahonia Aquifolium

A low growing plant with year-round pinnated, waxy green leaves that resemble holly. The plant bears dainty yellow flowers in early summer and a dark blue berry that ripens late in the Fall.

More About Oregon Grape

PACIFIC YEW (Cultivated)

Taxus species

Yews are evergreen shrubs or small trees with reddish-brown bark in thin flaking scales; leaves are dark green to yellow-green, shaped like a narrow sickle, stiff, 1.25 to 2.5 cm long, and pointed at the apex. Fruit is bright scarlet red or sometimes yellow and fleshy.

More About Pacific Yew

PEACE LILY (Houseplant)

Spalhiphyllum species

Leaves come directly from the root and are large for plant, elliptical in shape and narrow to a point. Leaves are 1 -5 feet long and up to 6 inches wide. Flowers are spathe-shaped and either white or green. Berries may be found in clusters but are rarely seen.

More About Peace Lily


Philodendron species

Fast growing plant with leathery, glossy leaves. Depending on species, may grow to 10-20 feet as a tree-like shrub.

More About Philodendron

POINSETTIA (Houseplant)

Euphorbia pulcherrima

Leaves are oval and 4-7 inches long. They are lobed. 

More About Poinsettia


Conium maculatum

Grows along streamside and ditch banks at all elevations, tolerates poorly drained soils. Can be found throughout the United States. Grows 4-10 feet tall. Hollow, branched, spotted stems with purple splotches. Leaves are fern-like. Single white taproot that resembles a carrot.  

More About Poison Hemlock


Toxicodendron rydbergii

Low shrub, rarely exceeds 4 feet in height. Prefers shady, wooded areas; found throughout the southwestern US

More About Poison Ivy


Epipremnum aureum

Commonly grown as an indoor potted plant and, in warm climates, as an outdoor ornamental. Heart-shaped or oval dark green leaves with yellow or white splotches, and slender stems. Grows as a vine.

More About Pothos

RUBBER TREE (Houseplant)

Ficus species

Narrow, leathery, dark-green leaves that are eight-twelve inches long.

More About Rubber Tree

SNOW ON THE MOUNTAIN (Native and Cultivated)

Euphorbia marginata

Oval, light-green leaves-upper ones striped and marginated white. Contains milky white sap that is irritating to the skin and mouth.

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Urtica dioica

Grows in moist, shaded woodland areas. Reaches about 4 feet tall at maturity, often grows in colonies. Leaves are lance-shaped and have sharp-toothed edges. Stems and leaves have hair-like structures.

More About Stinging Nettle

TULIP (Cultivated)

Tulipa species

Common garden plant grown from bulbs.

More About Tulip

UMBRELLA TREE (Houseplant)

Schefflera actinophylla/Brassaia actinophylla

The plant has a long stalk with glossy bright green leaves. The leaves are divided into 7-16 leaflets. Houseplant does not generally bloom.

More About Umbrella Tree


Parthenocissus quiquefolia

Woody vine, leaves are elliptical and occur in groupings of five leaflets with saw-toothed edges. Foliage changes from green in summer to orange in Fall. Planted in gardens as a ground cover or on fences.

More About Virgina Creeper

WART WEED (Native)

Euphorbia maculata

Stems are branching, hairy, and often pink to red in color. Can grow up to 12 inches tall, but often forms mats. Grows from a taproot. Leaves are ovate shaped.

More About Wart Weed


Cicuta douglasii

Grows along streamside, irrigation canals, and in moist pastures; seldom grows about 8500 feet in elevation. Grows 3 to 7 feet tall. Thick rootstocks have cross partitions at the base. Roots have separate chambers inside, and a musky odor. Leaves are lance-shaped, with toothed edges.

More About Water Hemlock


Aconitum columbianum

Grows 2-4 feet tall in damp shady places in upper elevation mountain areas. Has fleshy roots and stout stems. Leaves are dark green and deeply divided with multiple segments; leaves become smaller towards the top of the plant. Poisonous parts: all parts, especially roots and leaves.

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