A fellow blogger, Andrew – All Downhill From Here, posed a question about vines growing on trees.
English ivy and other evergreen vines can cause problems in trees, along with fast growing deciduous (lose their leaves in winter) vines like Kudzu. However, not all vines do harm to trees.
- English ivy (Hedera helix)
- Boston ivy (Parthenocissus tricuspidata )
- Japanese honeysuckle (Lonicera japonica)
- Chinese/Japanese wisteria (Wisteria spp.)
- Kudzu (Pueraria spp.)
These are just a few of the bad vines to allow to grow on trees. Evergreen and fast growing vines should be avoided or removed if possible. All vines can cause structural problems – The added weight can break branches along with the vine catching more wind, snow or ice than the tree is used to receiving, possibly causing it to topple. Some vines that start as a groundcover (such as ivy), form a dense mat covering the tree’s buttress or root flare. The vine often causes leaves and debris to pile up against the root collar and traps moisture against the trunk and root flare. This can cause many fungal and bacterial type diseases, as well as potential structural decay at the base of the tree. Deciduous vines aren’t necessarily any better than their evergreen counterparts. They, too have the capability of shading out the tree’s leaves, adding weight and even girdling (strangling) the tree’s limbs and trunk. Some common vines in this category; Chinese/Japanese wisteria, trumpet vine and pipevine. Trumpet vine and pipevine are native to the Midwest and usually confine their growth to trees at the edge of woods or those that are standing alone. Therefore, they don’t represent a threat to the forest overall, but they can take their toll on individual trees. It comes to personal preference if you want to go down this road.
Leave Them Be Vines:
Vines that are smaller and grow more slowly that can usually be allowed to grow on trees.
- Clematis species
- Virgin’s bower (native clematis – Clematis virginiana)
- Crossvine (Bignonia capreolata)
- Virginia creeper (Parthenocissus quincifolia)
- Carolina moonseed (Cocculus carolinus)
- Maypop / Purple Passion Flower (Passiflora incarnata)
- Poison ivy (Toxicodendron radicans)
Although Virginia creeper and crossvine can grow quickly and get large, I’ve never seen any tree so overgrown with them as to pose a problem even though crossvine can be evergreen. The clematis vines (including the native), Carolina moonseed and maypop climb by twining, however do not strangle the tree. Crossvine, Virginia creeper and poison ivy climb by using their aerial roots. People often confuse Virginia creeper and poison ivy. Just remember this little ditty:
“Leaves of three, leave it be. Leaves of five, leave it alive (or let it thrive).”
And before anyone jumps down my throat about the poison ivy, I would like to remind everyone that the Audubon Society considers poison ivy to be one of the top food sources for song birds, with about 63 species feeding on the berries. It’s so important, that nature has essential plant foods for birds. However, I digress. … Should you decide to let a smaller, slower-growing vine grow up a living tree, be prepared to manage the vine by cutting it back to keep it confined to the trunk and not allow it to grow on the limbs which could add weight and change the tree’s center of gravity as well as shade the tree’s leaves. Make sure that fallen leaves and other plant debris don’t collect at the bottom of the vine against the host tree or diseases may follow. Should a tree that is hosting a vine show signs of stress, the vine will have to go for the health of the tree. One last thought. Dead trees that are left standing (snags) can be used for vines. Just remember that this arrangement will be temporary, as the snag will eventually decay to the point of falling. Just make sure it won’t hit anything when it comes down.