Vines and Trees

By Jean Ann Feneis, Loudoun County Master Gardener, September 2010

Luckily, the first arborist who visited my farm when we bought it told me that vines growing on trees can cause damage and death to trees. Several of my older trees ahd trunks that were covered in English ivy, an invasive non-native. The arborist removed the vines by cutting the vines completely around the the trunk, but even carefully pulling out of the little tendrils of the ivy still caused some damage to the trunk bark. Ivy should be cut again at the base of the tree and all vines cleared away from the tree. It is best to wait until the vines above the cut die and have dried to make them easier to remove from the bark. If any ivy remains near the tree, watch for regrowth.

Although the ivy vine had not yet grown into the canopy of my trees (which smothers the tree by preventing sun from reaching the leaves and preventing photosynthesis) the arborist felt certain that the trees would decline more rapidly because of the vines. And, yes, unfortunately those trees have declined more rapidly although it has been thirteen years since the ivy was removed, and some trees will need to be removed from the property.

Ivy does not mature until it grows vertically when it will produce berries and multiply throughout neighboring forest trees. The photo to the right show the leaves of mature ivy that have enveloped a tree. The leaves have a different appearance than the immature ivy that creeps along the ground. Both the berries and the leaves of English ivy are poisonous to humans. However birds eat the berries and spread the seeds.

The added weight of vines on trees is devastating especially in wind and ice. It can cause large limbs to break and entire trees to go over.

Ivy covering a tree trunk keeps the trunk wet under the vines. This causes rot, girdling and other types of damage that will eventually kill the tree.

English ivy is an aggressive spreader and will soon be on the neighbors’ trees and into open forest property. English ivy also can carry pathogens that cause bacterial leaf scorch that afflicts shade trees. Bacterial leaf scorch spreads systemically and causes the slow decline and death of a tree.

To the eyes of many, the vines look beautiful growing over the trunks of trees and add a dimension of “old, stately and elegant,” but it’s quite likely that the vines will eventually kill the tree. While esteemed colleges and other venerable institutions describe and glorify their “ivy covered walls” the clinging tendrils of the vines are most likely eroding some housing materials, especially ruining finishes of window frames, roof eaves, siding and brick or stone walls.

These invasive vines can change the forest into dense monocultures and crowd out native plants including wildflowers, shrubs and young trees, then compete with the diverse plants needed for food and shelter for birds and other wildlife. Some of these culprits besides English ivy are Porcelain Berry, Oriental Bittersweet, Japanese Honey Suckle, Periwinkle, Climbing Euonymus (also called winter creeper) and Mile-A-Minute.