What is Killing Our Trees? Oriental Bittersweet ~ The First in a Series, de-Vining Bedford ~ Celebrate Arbor Day on Friday, April 29

~ Submitted by Bobbi Tornheim, Bedford Arbor Resources Committee member

There’s some pretty scary-looking stuff in the window box display in the Bedford Library, near the children’s section.  They’re pieces of Oriental Bittersweet vines, some bigger than a person’s leg — and they were cut down from our neighborhood trees!

Oriental Bittersweet was imported many years ago, probably because of its striking orange and yellow fall berries. You can still buy clusters of them in stores around town for holiday decorations. They look beautiful on your mantelpiece or formal dinner table. However, it has its dark side.

Bittersweet kills trees. The larger vines twist up tree trunks like snakes, squeezing out the tree’s ability to pull up nutrients.  The leaves eventually hitch a ride all the way up to the top, grabbing the life-giving sunlight from the tree’s own leaves. Sometimes, just the sheer weight of the bittersweet vines and leaves is enough to take a young tree down.

How to fix it? Easy. You can start at the ground, as close to the area where the vine emerges from the soil as possible. Using loppers, pruners, or a tree saw (depending on the size of the vine), just make two nearby cuts across the vine, and remove a small section between the cuts to prevent them from growing back together. All growth above the cuts will stop and die off over time. Eventually, the dead vines will dry and fall off.

But—the Bittersweet roots will put out more vines. Upkeep is equally important and easy. The new vines need to be nipped every few weeks until the Bittersweet plant root gives up. Once de-vined, I have watched some terribly sad and beaten down trees totally recover.

Besides cooling shade, trees make oxygen for us to breathe. Two mature trees can make enough oxygen in a year for a family of four. What is most important is that keeping mature trees alive and planting many new trees can actually slow climate change! With that in mind, the priority of protecting our current trees from invasive vines, as well as other modes of destruction, takes on new importance.