Poison ivy

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Poison ivy fruit

Poison ivy bud

Poison ivy bud

Poison ivy leaves

Poison ivy

Poison ivy

Poison ivy leaves

Poison ivy aerial roots

Poison ivy buds

Poison ivy aerial roots

Poison ivy fruit

Poison ivy aerial roots

Poison ivy bud and leaf scar

Poison ivy

Poison ivy fruit

Poison ivy

Poison ivy leaves

Poison ivy fruit

Poison ivy flower

Poison ivy flowers

Morphology

Trunk

Stems climbing, clambering, or erect, spreading by underground suckers; branches often with aerial roots; bark gray, smooth to somewhat ribbed; wood yellowish brown, soft.

Twigs

Light brown, pubescent, flexible; leaf scars crescent-shaped; buds brown, ovoid, .16 to .2 inch, scales tawny-tomentose.

Leaves

Deciduous, alternate; petiole 2.4 to 8 inches, pubescent; leaflets 3: lateral petiolules .6 to 1.2 inch, terminal petiolule .8 to 2 inches; blade ovate to elliptic, 2 to 7 inches long, 1.6 to 7.6 inches wide, base truncate, often inequilateral in lateral leaflets, margins entire or irregularly serrate, dentate, lobed, or incised; apex acute to acuminate, abaxial surface light green, sparsely to moderately pubescent, especially along veins, adaxial surface green to yellowish green, glabrous or glabrate.

Flowers

Inflorescences are axillary on current-year growth, lax to spreading or erect, panicle-like, narrowly to broadly ovoid, 2 to 4 inches, 10-50-flowered; peduncles .2 to .8 inch, pubescent; pedicels .04 to .1 inch, sparsely pubescent. Flowers unisexual, radially symmetric; sepals 5, connate proximally, green, ovate to triangular; petals 5, distinct, greenish yellow, ovate, .1 to .12 inch; staminate: stamens 5; pistillate; pistil 1, styles 3; stigmas 3, head-shaped.

Fruit

July to September; drupes, cream to yellowish white, spherical, .12 to .2 inch, glabrous or with few scattered hairs, glossy; stone 1, yellow or yellowish white, spherical, low-ribbed.

Ecology

Habitat

Dry or moist woods, stream banks, pond and lake margins, roadsides, prairie thickets, shaded, disturbed areas.

Distribution

East 2/3 of Kansas

Practical Information

Toxicity

All parts of this plant can cause allergic dermatitis when in contact with skin. A red rash, blisters and itching typically occur within 12 to 24+ hours and can spread if the resinous oil is not washed off. Contact with contaminated clothing or animal hair can cause symptoms. Some people are more sensitive than others. One should immediately wash with cold water after contact.

Additional Notes

Synonyms

Alternative scientific names that have been used for this plant.