Allowing vines to climb up trees is never a good idea. Vines like English ivy (Hedera helix), which start by covering the ground often end up quite literally “glueing” themselves to the trunks of trees as they climb. This can restrict tree diameter growth causing the tree to slowly decline over time.
Image above shows English ivy consuming a large black walnut tree.
As vines grow into the canopy, they can cause structural damage as well. The added weight may result in limbs breaking, especially when loaded with snow and/or ice. A tree covered in vines will also capture more wind, possibly leading to the entire tree failing.
Vines covering the trunk flare, the base of the tree where it meets the ground, can form a thick blanket of debris. This debris can trap excess moisture against the trunk and root collar thus increasing the potential for root decay fungi that can cause severe structural defects. The excess debris and moisture can also interrupt the tree’s ability to transport sugars to the roots.
Image above shows English ivy vines covering the trunk of an oak tree.
Vines growing on trees can hide dangerous structural defects such as dead or broken limbs and decayed areas as well. Over time these areas can become weak causing the limb or trunk to fail possibly resulting in personal injury or property damage.
Twining vines like Chinese wisteria (Wisteria sinensis) and Oriental bittersweet (Celastrus orbiculatus) grow by wrapping themselves around trunks and limbs. As the vines and the tree grow in diameter they can eventually girdle the tree. Native vines, such as poison ivy (Toxicodendron radicans) and Virginia creeper (Parthenocissus quinquefolia), grow up the trunk without twining around it and therefore do not strangle or girdle the tree.
Image above shows Oriental bittersweet twining up a large, multi-trunked willow tree
When vines grow up into the crowns of trees the added foliage can shade the tree’s leaves, robbing the tree of sunlight necessary for photosynthesis. Shading a tree’s foliage is as severe a problem as girdling the trunk. Invasive vines often grow much faster than trees and can quickly overtake a tree’s canopy
Invasive climbing and twining vines pose a threat to the health and safety of your trees. There are numerous species, so it is important to learn to identify them. The Pennsylvania Department of Conservation and Natural Resources lists 12 different invasive vine species found in Pennsylvania. Those commonly found in the central part of the state include:
- Oriental bittersweet
- English ivy
- Japanese honeysuckle
- Mile-a-minute
- Chinese wisteria
To control climbing vines without harming the tree, sever the vines at the base of the tree. Don’t try to pull them out of the canopy. This could pull bark off the tree or worse, break limbs and pull them down upon you. Once the vines have been severed, the portion left in the canopy will die. Over time, the vines will desiccate and gradually fall apart.
Above images show before and after photos of a vine removal project on a Norway spruce tree.
To prevent the severed vines from regrowing, the vine’s roots could be pulled up or a better alternative is to treat the cut surface of the vines with a herbicide. The herbicide will prevent the stump from resprouting and help control the roots. If herbicides aren’t used, vines will need to be periodically cut and pulled off the tree.
Image above shows cut vines treated with a herbicide to prevent resprouting.
If any of your trees are host to strangling vines the arborists at Cutting Edge can help. We can safely control the vines without harming the tree. Additionally, we have certified pesticide technicians who can treat vines to help prevent regrowth. Contact us today for a free estimate.
Written by: David R. Jackson, ISA Certified Arborist, Cutting Edge Tree Professionals