Is English Ivy Bad for Your Trees?
Yes, English ivy is bad for trees in Pennsylvania, even though it does not feed on them directly. The Pennsylvania Department of Conservation and Natural Resources (DCNR) says the vine kills branches by covering their leaves and blocking photosynthesis as it climbs toward the light, and that its sheer weight makes trees more likely to blow over in bad weather. The National Park Service notes the vine can climb to 90 feet, clinging with its roots until it encases a tree.
The risk is not only structural. DCNR's fact sheet identifies English ivy as a reservoir for bacterial leaf scorch, caused by the bacterium Xylella fastidiosa, which it calls a threat to native trees. Penn State Extension lists oak, elm, red maple and sycamore among the trees that disease infects and says it has no permanent cure. This post covers how ivy harms trees, how to remove it without injuring the bark, and when a tree covered in ivy needs a closer look.
How Does English Ivy Damage a Tree?
English ivy is an evergreen climbing vine from Europe with waxy, dark green leaves and conspicuous white veins, according to DCNR and the National Invasive Species Information Center. On a tree, it causes harm in three ways.
It shades out the tree's own leaves
As ivy climbs into the crown, DCNR says it covers the tree's leaves and kills branches by preventing photosynthesis. A tree losing branches to shade has less capacity to feed itself.
It adds weight and wind resistance
Because the vine is evergreen, that extra load stays on the tree through winter storms as well as summer ones. DCNR says the sheer weight of ivy makes trees susceptible to blowing over during inclement weather, and the Western Pennsylvania Conservancy notes it can damage or kill weakened trees, which then become susceptible to wind or ice storms. Our posts on why trees split during high winds and how dangerous ice-covered trees are near homes explain what that extra load does.
It hides problems
A trunk wrapped in ivy is hard to inspect. Cracks, cavities, fungus and decay at the base can go unnoticed until something fails.
Why Does Bacterial Leaf Scorch Matter Here?
Bacterial leaf scorch is a disease caused by the bacterium Xylella fastidiosa, which lives in a tree's water-conducting vessels. Penn State Extension describes symptoms that begin in mid to late July, with leaf edges browning toward the center and a band of dark reddish-brown tissue separated from the green by a narrow yellow border.
Penn State lists oak, elm, red maple, sycamore, mulberry and sweetgum as hosts and notes the bacterium has been documented on pin and red oaks throughout eastern Pennsylvania. Spittlebugs, treehoppers and leafhoppers carry it from plant to plant. There is no permanent cure: Penn State says tetracycline injections temporarily relieve symptoms in the year they are applied but do not cure the tree.
Because DCNR identifies English ivy as a reservoir for the bacterium, a yard full of ivy under oaks and maples gives those insects a nearby source. Removing the ivy will not cure a tree that is already infected, but it takes away one reservoir close to the trees you care about.
How Do You Remove English Ivy From a Tree Safely?
Cut it, do not pull it. DCNR says climbing vines can be severed near the ground to kill the upper portions, and North Carolina State Extension recommends cutting the stems at the ground and removing the vines from the tree as high as you can easily reach. A practical sequence:
Cut every vine stem where it meets the trunk near the ground. Some stems can be thick, so use loppers or a small saw.
Peel the vines off the lower trunk as high as you can easily reach, working carefully so you do not strip bark with them.
Pull the ivy growing along the ground around the base of the tree. DCNR notes groundcover vines can be pulled by hand, though not without difficulty.
Leave the vines higher in the tree. Once cut off from their roots, they die in place.
Check the base every few months for new stems climbing back up.
Wear gloves and long sleeves. The National Park Service recommends pulling, cutting, and treating ivy when fruit is not present, which also keeps you from spreading seeds. For large ground patches, North Carolina State Extension points to research comparing triclopyr and glyphosate, where results depended on timing and formulation, so follow the product label closely or hire a licensed applicator.
Why Does Ivy That Reaches the Canopy Spread Faster?
Ivy changes once it climbs. The National Park Service explains that juvenile English ivy has heart-shaped leaves with three to five pointed lobes, while mature plants develop unlobed leaves. Climbing mature plants produce flower clusters in summer that become dark purple berries in winter and spring, and birds spread the seeds.
DCNR adds that in sufficient light, the vine produces yellow-green flower clusters in the fall. In other words, the climbing vines on your trees are the ones producing berries for birds to spread. Cutting climbing vines at the base stops that seed production along with the damage.
When Does an Ivy-Covered Tree Need Professional Help?
Once the ivy dies back, take a hard look at the tree. Call for an inspection if you see:
Dead branches in the upper crown where the ivy was thickest
A lean that was hidden by the vines
Cracks, cavities, or soft wood at the base
Dead ivy mats hanging over a roof, driveway or power line
Dead limbs can be removed through pruning, and a tree that has been badly weakened may need to come down before the next storm. Our guide to spotting a hazardous tree before it becomes a crisis helps you judge the urgency, and how to prevent tree damage before storms covers other preparation.
FAQ
Does ivy kill trees?
It can. DCNR says ivy kills branches by covering leaves, and its weight makes trees more likely to blow over in bad weather.
Should I pull ivy off the trunk?
Cut it at the base first. DCNR says severing climbing vines near the ground kills the upper portions, and pulling vines from high on the trunk risks tearing bark.
Is English ivy invasive in Pennsylvania?
Yes. DCNR includes English ivy in its invasive plant fact sheets, describing it as an invasive vine that infests woodlands, forest edges, fields, and hedgerows.
Where did English ivy come from?
The National Invasive Species Information Center lists its native range as Europe and says the earliest records of it growing wild in the United States date to the 1870s, after it arrived through the nursery trade.
Will the dead ivy fall out of the tree?
Vines left high in the tree die once they are cut from their roots, and you can leave them there. If large dead mats hang over a roof, walkway or power line, have them removed rather than waiting.
Can bacterial leaf scorch be cured?
No. Penn State Extension says tetracycline injections temporarily relieve symptoms in the year they are applied but do not cure the tree.
Tree Pruning and Removal From Brinko Tree Service
Brinko Tree Service is based at 1010 Sunset Blvd in Harrison City and serves Westmoreland and Allegheny Counties with nearly 20 years of experience. When ivy has left a tree with dead limbs or a hidden weakness, the team provides pruning and trimming to remove dead or hazardous branches and tree removal when a tree cannot be saved, along with brush chipping and cleanup. Brinko is fully licensed and insured, follows OSHA and ANSI safety regulations with an OSHA safety site supervisor on every job site, and offers free estimates.
Visit Brinko Tree Service or call 412-373-7450 today. Contact us for more information.
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