All green is not good. In fact, the type of green is very important. Invasive plants are green, but they are a detriment to our environment by changing the natural succession in our urban forest.
“English Ivy (Hedera helix) is an aggressive invader that threatens all vegetation levels of forested and open areas”, according to the National Park Service. It is also listed as an invasive plant in Pennsylvania and 19 other states by the USDA Forest Service. Ivy is often the cause of unhealthy trees that eventually become hazards to homes and properties, and here are some reasons why:
Ivy running up trees will cover branches and prevent leaf-out, marring the tree’s appearance and its health. Loss of host tree vigor, evident within a few years, is followed by death a few years later. The cost of tree removal can be substantial.
The weight of mature ivy vines makes infested trees susceptible to blow-over during storms.
Ivy can transmit bacterial leaf scorch, which threatens native elms, oaks and maples.
Ivy creeps aggressively beyond its intended space into neighboring yards, parks and forests. Mature vines live for years, and develop seeds which birds disperse to other areas.
Its dense growth smothers native plants, preventing sunlight from reaching leaves.
Ivy is NOT a good bank stabilizer because its roots are shallow and out-competes better, deeper rooted bank stabilizers.
HOW TO CLEAR IVY FROM TREES
First, remove ivy from trees and then remove ivy from the ground. Use loppers or a pruning saw to cut through each vine at shoulder height and at ankle height. Strip the ivy away from the tree between the two cuts. Be careful not to damage the bark.
Next, pull up as much ivy as possible around the base of the tree. Extend the pulled area to at least six (6) feet from the tree’s base all the way around to prevent ivy from climbing back up the trunk. Cautiously dispose of the ivy as it re-sprouts easily.
If chemicals are used, “paint” the cut side of the vine with glycophosphate (available in a variety of forms in garden stores) immediately after cutting.
REPLANT WITH NATIVE GROUNDCOVERS
Suggestions include: wild ginger, mayapple, partridge berry, foamflower, creeping phlox, wintergreen, Allegheny (or native) pachysandra, bearberry, asters, and Christmas fern (evergreen). Avoid other vines around trees - their effect can be similar to ivy.
Invasive removal is not a cosmetic issue; the health of our native habitat and magnificent trees are at serious risk. Without prompt action, thousands of trees in our area alone will be toppled or killed by ivy and other invasive vines. We are privileged to live in such a beautiful environment - but with this privilege comes the obligation to care for it. Please do your part before it’s too late!