Poison Ivy

Toxicodendron radicans

Copyright, James Manhart

Poison Ivy is one of the best-known, and probably the most-hated, plant in Virginia. Because most people are allergic to its sap, Poison Ivy can cause a nasty rash and blisters on the skin.

Poison Ivy is most easily recognized by it's leaf pattern. Although it's color varies with the seasons, it always has clusters of three leaves.

Some leaves are smooth-edged and some are notched. Some are shiny, and some are dull. In the Spring, leaves start out shiny and red. This may help keep insects away. In the Summer, leaves are usually green. In the Fall, leaves change colors with the trees. They can turn yellow, orange, and red before they drop off.

www.poison-ivy.org

Virginia Ducey, Institute for Systematic Botany ,Department of Biology, University of South Florida

Copyright, Dan Tenaglia, Missouriplants.com

Poison Ivy can grow in just about any environment. It is most common, though, on edges. Edges of forests, edges of roads, edges of streams and lakes, and edges of lawns are where you will see huge amounts of Poison Ivy.

Poison Ivy can grown in many ways also. It can creep along the ground, growing new roots as it spreads. It can grow as a vine, up tree trunks or fenceposts. It can also grow as a bush.

Poison Ivy has very tough roots, and once established, it is very difficult to get rid of.

www.poison-ivy.org

www.poison-ivy.org

www.poison-ivy.org

 

Poison Ivy grows flower clusters up to three inches long, with yellowish-white or greenish-white flowers. Flowers bloom from May to July.

The flowers will give way to berry-like fruits which are whitish-gray. These fruits are eaten by many birds, raccoons, and other animals.

Some birds, such as the Northern Cardinal and American Goldfinch, also use thread-like hairs from the Poison Ivy vine to build their nests.

Copyright, Dan Tenaglia, Missouriplants.com

The rash that Poison Ivy causes with humans is from the sap, which has an oil called "urushiol" in it. Urushiol only comes out of the plant where it is damaged; however, Poison Ivy is very fragile and breaks easily. Wind, animals, or chewing insects can cause urushiol to be released.

When urushiol gets on your skin, your skin absorbs it slowly. Your skin will then have a reaction, resulting in a red rash with blisters. If urushiol gets on your dog or clothes, it can later transfer to you!

Not everybody is allergic to Poison Ivy, and some people are more allergic than others.

Copyright, James Manhart

Poison Ivy often grows with certain plants. It will climb almost any tree, especially American Sycamore, American Elm, Southern Red Oak, Loblolly Pine, American Beech, and White Oak.

Poison Ivy grows with other vines as well, such as Virginia Creeper and Japanese Honeysuckle. These vines will grow on each other, as well as the tree or shrub they are climbing.

Poison Ivy is also a food source for animals. White-tailed Deer, Muskrat, and Eastern Cottontail eat the leaves and stems. Many birds, including crows, bluebirds, and turkeys eat the fruit. Insects munch on the leaves.

Poison Ivy's foliage (leaves and stems) provides shelter for small animals.

www.poison-ivy.org

Relationships in Nature:

Animals Using as Food Source

Animals Using as Shelter

Associations With Other Plants

OTHER

White-tailed Deer

Wood Frog

Virginia Creeper

Common Crow D

Common Crow

Bullfrog

Japanese Honeysuckle

Raccoon D

Raccoon

Red-backed Salamander

American Sycamore

Pileated Woodpecker D

Pileated Woodpecker

Meadow Vole

American Elm

Wild Turkey D

Wild Turkey

Least Shrew

Loblolly Pine

American Robin D

American Robin

Horned Fungus Beetle

Willow Oak

Green Hawthorn H

Northern Bobwhite

Patent-leather Beetle

Mockernut Hickory

Silver Maple H

Eastern Bluebird

Eastern Chipmunk

Red Maple

Japanese Honeysuckle Pa

Gray Catbird

Leopard Slug

Yellow Poplar

Carolina Chickadee D

Carolina Chickadee

Eastern Box Turtle

Witch Hazel

Willow Oak H

Muskrat

Five-lined Skink

Virginia Pine

Eastern Cottontail

American Dog Tick

Sassafras

Eastern Forest Snail

Wild Turkey

American Beech

Carolina Wren

Rabid Wolf Spider

Eastern White Pine

Yellow-bellied Sapsucker

Northern Cardinal

Trumpet Creeper

Purple Finch

American Goldfinch

Wild Grape

Northern Mockingbird

American Toad

Greenbrier

Dark-eyed Junco

Goldenrod Spider

Silver Maple

White-throated Sparrow

Eastern Gray Squirrel

Spotted Jewelweed

European Starling

Pipevine Swallowtail

Virginia Rose

Relationship to Humans:

Most people's interactions with Poison Ivy are negative. Poison Ivy rashes are very uncomortable, and can even be serious for people who are highly allergic. However, many consider Poison Ivy's foliage to be beautiful, especially in the fall. Some people plant Poison Ivy in their gardens or along forest edges to add color. Poison Ivy can also attract many songbirds and deer. Deer like Poison Ivy so much, it may keep them from eating other garden plants.

SCIENTIFIC CLASSIFICATION

KINGDOM
Plant
PHYLUM
Magnoliophyta
CLASS
Magnoliopsida
ORDER
Sapindales
FAMILY
Anacardiacae
GENUS
Toxicodendron
SPECIES
Toxicodendron radicans

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