USDA, NRCS
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English Ivy
Hedera helix
Origin: Europe, Western Asia and Northern Africa
Background
European immigrants likely introduced English ivy to the
United States. It is extremely popular and widely planted
because of its evergreen foliage and dependability as a
year-round ground cover. Although widely recognized as a
serious pest of natural areas, it continues to be sold as
an ornamental plant in the United States.
Distribution and Ecological Threat
English ivy occurs throughout the eastern United States,
across the southern states and up to Washington State. It
is one of the most abundant and insidious invasive plants,
as it threatens all vegetation levels of forested and open
areas, growing along the ground as well as into the tree
canopy. English ivy infests woodlands, forest edges,
fields, hedgerows, coastal areas, salt marsh edges and
other upland areas, especially where some soil moisture is
present. As a ground cover, the dense growth and abundant
leaves form a thick canopy just above the ground that
prevents sunlight from reaching herbs and seedlings. Vines
that climb up trees slowly kill the tree from the base
upwards by enveloping branches and twigs, blocking
sunlight, causing branch and eventual tree death. The
added weight of vines also makes trees susceptible to
blowing over during storms. English ivy has been confirmed
as a reservoir for bacterial leaf scorch (Xylella
fastidiosa), a harmful plant pathogen that affects a
wide variety of native and ornamental trees such as elms,
oaks and maples.
Description and Biology
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Plant: an evergreen climbing vine in the ginseng family
(Araliaceae). Vines attach to the bark of trees and
other surfaces by way of numerous, small, root-like
structures, which exude a glue-like substance; older
vines can reach a foot in diameter.
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Leaves: dark green, waxy, somewhat leathery, arranged
alternately along the stem; leaf forms are extremely
variable with the most recognized leaf form being
three-lobed.
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Flowers, fruits and seeds: when sufficient light is
available, umbrella-like clusters of small,
greenish-white flowers are produced in the fall on
flowering branches that extend out at right angles from
clinging vines; fruits and are black with a fleshy
outer layer and mature during the following spring;
seeds are stone-like.
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Spreads: reproduces vegetatively and by seed, which is
dispersed to new areas primarily by birds. English ivy
contains glycosides that cause some birds to vomit and
disseminate seeds. New plants grow easily from cuttings
or stem fragments that make contact with the soil.
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Look-alikes: Boston ivy (Parthenocissus
japonicus) is sometimes confused with English ivy.
Prevention and Control
Do not plant English ivy. Vines on the ground can be
pulled up by hand, with some difficulty and bagged and
disposed of as trash. Vines climbing up trees should be
cut to kill upper portions and relieve the tree canopy.
Portions of vines rooted in the ground will remain alive
and will need to be treated with herbicide or cut
repeatedly until no re-growth occurs. A systemic herbicide
like triclopyr may be applied to foliage or cut stems.
There are no biological controls currently available for
English ivy.
Native Alternatives
Vines:
Virginia creeper (Parthenocissus
quinquefolia)
Britt Slattery, USFWS
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crossvine (Bignonia
capreolata)
Britt Slattery, USFWS
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Groundcovers (use alone or mix for diversity and
sustainability):
wild ginger (Asarum
canadense)
Britt Slattery, USFWS
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lady fern (Athyrium
filix-femina)
Kenneth J. Sytsma, UWI
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foam flower (Tiarella
cordifolia)
Britt Slattery, USFWS
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partridgeberry (Mitchella
repens)
Britt Slattery, USFWS
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creeping phlox (Phlox
stolonifera)
Britt Slattery, USFWS
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evergreen wood fern
(Dryopteris marginalis or
intermedia)
Emmet J. Judziewicz, UWI
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