Eastern Poison Ivy Toxicodendron radicans
Other Common Name(s):
Previously known as:
- Rhus radicans
- Phonetic Spelling
- toks-ee-ko-DEN-dron RAD-ee-kans
- This plant has high severity poison characteristics.
- See below
- Description
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Poison ivy is native throughout the United States and much of southern Canada and can be found in a wide variety of locations including dry or wet woodlands, thickets, valleys, clearings, fence rows, roadsides and waste ground. It can appear as a bushy, erect or trailing shrub in sunny areas or as a woody climbing vine. The climbing vines have aerial rootlets. All parts of the plant contain a toxic oil called urushiol that causes significant and long-lasting skin irritations (allergic dermatitis) in most human beings. Infection can occur from direct contact with the plant, indirect contact (e.g., dog, rake or shoes) or from breathing smoke from a fire of plant material. Some humans seem to be immune.
When it grows as a woody shrub, it can reach lengths of 6 feet; when it grows as a vine, it can reach 60 to 150 feet tall and climb high on trees, walls, and fences or trail along the ground. Birds, reptiles, deer, and amphibians can eat the plant and its berries and also use the plant as shelter. A variety of insects feed on the flowers of poison ivy too – from beetles to flies, bees, wasps, ants, and butterflies. Due to its wildlife benefits, it can be left alone in native areas with low human activity.
Poison ivy leaves are compound leaflets in groups of three, a trait that can reliably distinguish it from a number of similar native vines. The middle leaflet is longer than the outer two. It’s hard to describe poison ivy leaflets because their shape and size vary from smooth, rounded edges to serrated edges to shallowly lobed edges, but its leaflets are always in groups of three. Poison ivy leaves are shiny, bright green, and turn an attractive red or reddish yellow in the fall. The bark is dark gray and densely covered in aerial roots.
Poison ivy can be removed by either mechanical means– such as repeated mowing or pulled with gloved hands– or with certain herbicides applied to freshly cut stumps. Only use herbicide as a last resort.
Insects, Diseases, or Other Plant Problems: Poison ivy, is the ultimate weed that no one wants. As the saying goes, “Leaflets three, let it be." Do not touch any part of a poison ivy plant. All parts of the plant contain volatile oils that can cause significant skin irritation on direct or indirect contact. Do not burn plant materials because contact with smoke from the burning materials can be just as toxic as touching the plants. Breathing the smoke can be even more hazardous.
- Profile Video:
- See this plant in the following landscape:
- Cultivars / Varieties:
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- Tags:
- Cultivars / Varieties:
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- Tags:
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Attributes:
- Genus:
- Toxicodendron
- Species:
- radicans
- Family:
- Anacardiaceae
- Life Cycle:
- Perennial
- Woody
- Recommended Propagation Strategy:
- Seed
- Country Or Region Of Origin:
- Southern Canada, North America to Central America, Central China
- Distribution:
- All United States except Hawaii, California, and Alaska
- Wildlife Value:
- Although this plant can cause severe skin irritations on some people, the fruits are readily eaten by songbirds and woodpeckers. White-tailed deer and rabbits browse the plant and reptiles and amphibians use it for shelter. The flowers are pollinated by and act as a food source for a wide variety of insects.
- Play Value:
- Wildlife Cover/Habitat
- Wildlife Food Source
- Dimensions:
- Height: 1 ft. 0 in. - 3 ft. 0 in.
- Width: 1 ft. 0 in. - 3 ft. 0 in.
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Whole Plant Traits:
- Plant Type:
- Native Plant
- Perennial
- Poisonous
- Shrub
- Vine
- Weed
- Woody Plant Leaf Characteristics:
- Deciduous
- Habit/Form:
- Ascending
- Climbing
- Creeping
- Multi-stemmed
- Spreading
- Growth Rate:
- Rapid
- Maintenance:
- High
- Texture:
- Medium
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Cultural Conditions:
- Light:
- Dappled Sunlight (Shade through upper canopy all day)
- 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:
- Clay
- High Organic Matter
- Loam (Silt)
- Sand
- Shallow Rocky
- Soil pH:
- Acid (<6.0)
- Alkaline (>8.0)
- Neutral (6.0-8.0)
- Soil Drainage:
- Moist
- Occasionally Dry
- NC Region:
- Coastal
- Mountains
- Piedmont
- USDA Plant Hardiness Zone:
- 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b
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Fruit:
- Display/Harvest Time:
- Fall
- Fruit Type:
- Drupe
- Fruit Width:
- < 1 inch
- Fruit Description:
- Each flower is replaced by a drupe that contains a single seed (stone). This drupe is dull white and about ¼ inch across; it has a smooth waxy surface. The large seed is ovoid in shape and dull white; there are a few grey stripes across its surface. The drupes mature during the fall and can persist through the winter.
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Flowers:
- Flower Color:
- Green
- White
- Flower Inflorescence:
- Panicle
- Flower Bloom Time:
- Spring
- Flower Petals:
- 4-5 petals/rays
- Flower Size:
- < 1 inch
- Flower Description:
- Across from the compound leaves, panicles of yellowish green flowers are sparingly produced. These panicles are up to 4 inches long and across; they are often irregular in shape. Each flower is about ¼ inch across, consisting of 5 green petals, 5 stamens, 5 sepals, and an ovary with a stout style. The petals are triangular-shaped and recurved, while the sepals are smaller in size and deciduous.
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Leaves:
- Woody Plant Leaf Characteristics:
- Deciduous
- Leaf Color:
- Gold/Yellow
- Green
- Deciduous Leaf Fall Color:
- Red/Burgundy
- Leaf Type:
- Compound (Pinnately , Bipinnately, Palmately)
- Leaf Arrangement:
- Alternate
- Other/more complex
- Leaf Shape:
- Cordate
- Elliptical
- Ovate
- Leaf Margin:
- Dentate
- Entire
- Lobed
- Hairs Present:
- No
- Leaf Length:
- 3-6 inches
- Leaf Width:
- 1-3 inches
- Leaf Description:
- Leaves emerge with a shiny reddish tinge in the spring and turn a dull green as they age, eventually turning shades of red or purple in the fall before dropping. Three leaflets that are pointed often with a notch on the edge. The middle leaflet has a short period or stem and is longer than the outer two. Leaflets can be 2 to 6 inches long and may be toothed or have smooth edges. The stems of the two side leaflets are always directly opposite to each other. The sets of three leaflets are never directly opposite each other on the vine.
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Stem:
- Stem Color:
- Green
- Red/Burgundy
- Stem Is Aromatic:
- No
- Stem Buds:
- Hairy
- Stem Cross Section:
- Round
- Stem Form:
- Straight
- Stem Surface:
- Hairy (pubescent)
- Stem Description:
- The stems are initially light reddish green, but they eventually become brown and woody. The woody stems are often covered with coarse brown hairs, but sometimes they are hairless. As a vine, aerial rootlets develop along the stems; these rootlets can cling to tree bark, fences, walls, and other objects.
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Landscape:
- Landscape Location:
- Meadow
- Naturalized Area
- Woodland
- Landscape Theme:
- Native Garden
- Attracts:
- Butterflies
- Moths
- Songbirds
- Resistance To Challenges:
- Deer
- Drought
- Problems:
- Contact Dermatitis
- Weedy
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Poisonous to Humans:
- Poison Severity:
- High
- Poison Symptoms:
- All parts of poison-ivy contain resinous compounds called urushiols, the highest concentrations in the leaves and bark as well as younger leaves. When urushiols directly come into contact with the skin or are inhaled via smoke, they cause inflammation, itching, and blistering. The skin irritation is significant and long-lasting for most humans.
- Poison Toxic Principle:
- Urushiol
- Causes Contact Dermatitis:
- Yes
- Poison Part:
- Bark
- Flowers
- Fruits
- Leaves
- Roots
- Sap/Juice
- Seeds
- Stems