Hedera helix L.
English Ivy| Threat Level | Category |
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| Established | Vine |
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Similar Species May be confused with the following native and/or non-native species. Landscape Alternatives lists native horticultural substitutes |
Vitis spp. Landscape Alternatives |
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Description
Height
English ivy is an evergreen woody vine climbing to 90 feet (28 m) by clinging aerial roots and trailing to form a dense groundcover.Stem
Woody stems remain slender vines when growing as a ground cover and enlarge to 10 inches (25 cm) in diameter when climbing infested trees and rocks via many fine to stout aerial rootlets. Vines are pale green (sometimes reddish tinged) and root at the nodes. Stems become covered with gray-brown shiny bark, segmented by encircling and raised leaf scars and roughened by tiny ridges. The bark matures light gray to brown, bumpy and gnarly, with aerial rootlets developing along the side where it clings to vertical structures. Aerial rootlets exude a gluelike substance. Older vines sometimes grow together where crossed.Leaves
Leaves are alternate on the stem, and shapes vary according to age, with typical juvenile plants having three to five pointed lobes and mature plants broadly lanceolate and unlobed, 2 to 4 inches (5 to 10 cm) long and 2.5 to 5 inches (6 to 12 cm) wide. Each leaf is thick and waxy, smooth and hairless, dark green with whitish veins radiating from the petiole and pale green beneath. Petioles are up to 6 inches (15 cm) long, pale green and often reddish tinged.Flowers
From June to October, terminal, hairy-stemmed, umbel clusters of small, greenish-yellow flowers develop on mature plants. Flowers have five thick and pointed petals, 0.1 inch (3 mm) long, and each petal radiates from a five-sided domed green floral disk, 0.1 inch (3 mm) wide, tipped by a short pistil.Fruit and seeds
Clusters of spherical drupes, 0.2 to 0.3 inch (7 to 8 mm) ripen from pale green in late summer to dark blue to purplish in late winter to spring.Images
Photo: Forest & Kim Starr, U.S. Geological Survey, Bugwood.orgMore images of Hedera helix
Life History
English ivy has thick dark-green leaves with whitish veins and three to five pointed lobes when young. It matures at about 10 years into erect plants or branches with unlobed leaves and terminal flower clusters that yield purplish berries. Toxic to humans when eaten and triggers dermatitis in sensitive individuals. English ivy is in the Araliaceae or Ginseng family.Ecology & Habitat
English ivy thrives in moist open forests, but with the exception of wet areas, it is adaptable to a range of moisture and soil conditions, including rocky cliffs. Its shade tolerance allows early growth under dense stands, and it becomes adapted to higher light levels with maturity. Plants amass on infested trees, decreasing their vigor, and increasing the chance of windthrow. English ivy serves as a reservoir for bacterial leaf scorch that infects oaks (Quercus spp.), elms (Ulmus spp.), and maples (Acer spp.). It spreads through bird-dispersed seeds and colonizes by trailing and climbing vines that root at the nodes. The drupes are mildly toxic, discouraging over consumption by birds.Origin and Distribution
English ivy was introduced from Europe in colonial times. It is a traditional ornamental and is still widely planted in landscapes. It is a source of varnish resin, dye, and tanning substances.Other states where invasive: AZ, CA, DC, DE, GA, KY, LA, MD, NC, NJ, OR, PA, RI, SC, VA, WA, WI, WV. Federal or state listed as noxious weed, prohibited, invasive or banned: OR, WA.
Source: Information on this plant page is derived primarily from James H. Miller's Nonnative Invasive Plants of Southern Forests, USDA Forest Service.
Management Recommendations
Herbicidal Controls
Foliar Spray Method
Thoroughly wet all leaves (until runoff) with one of the following herbicides in water with a surfactant (July to October for successive years):Triclopyr as a 3- to 5-percent solution (12 to 20 ounces per (3-gallon mix) or a glyphosate herbicide as a 2-percent solution (8 ounces per 3-gallon mix). Use a string trimmer to reduce growth layers and injure leaves for improved herbicide uptake.