An invasive vine strangles a young tree.

by Sue Ann Rybak

Spring is finally here, and it’s the perfect time to hit the trails or do a little gardening.

In Philadelphia, we are lucky to have Fairmount Park, one of the largest city-owned parks in the country. It contains more than 9,000 acres of rolling hills, gentle trails and shaded woodland. But while almost everyone appreciates its breathtaking landscapes, very few residents lend a hand to maintain its natural beauty.

One of the easiest and most inexpensive ways of maintaining a beautiful, flourishing woodland is to cut back invasive vines. Dense thickets of invasive vines limit plant diversity, which reduces food and shelter for wildlife. Invasive vines shade out native seedlings resulting in fewer trees. Reduced tree cover also reduces storm water interception.

The Local sat down with Ken LeRoy, a certified arborist who has worked at the Morris Arboretum and occasionally teaches at Mt. Airy Learning Tree.

“Everyone is talking about invasive trees and no one is talking about invasive vines,” LeRoy said.

“Unfortunately, we’re not doing anything to manage invasive vines in our cities or suburbs. I would really like to see patches of woods in our city given some priority because we talk a lot about trees and how great trees are – but we don’t do anything to maintain or manage our woods.”

LeRoy said invasive vines are especially problematic in young woods. He said the vines wrap around the trees and strangle them. LeRoy added that while vines are an important part of the environment, several invasive vines like English ivy and grape vines are smothering forest by not allowing the forest to regenerate tree growth.

“We are really losing opportunities to absorb carbon in our woods by allowing vines to just overtake everything,” LeRoy said.

He said invasive vines grow rapidly, especially in disturbed areas where trees have been cut, and vines such as bittersweet are long flowering and are easily spread by birds and squirrels.

“I am really campaigning for vine management,” LeRoy said. “It’s not that I want to eliminate all vines, I want the woods to grow.”

He said invasive vines such as English ivy grow fast but they don’t grow fat.

“They put their energy into sprawling,” LeRoy said. “They really benefit from a higher carbon dioxide content in the atmosphere because it grows more rapidly. If you give a tree a hundred years, it’s going to grow 50 to 60 inches in diameter and grow a hundred feet tall. But if you give a hundred years to a vine, it’s not going grow in diameter – it’s going to sprawl.”

LeRoy hopes that this article will encourage residents to cut back invasive vines in their backyard and volunteer to help maintain small patches of woods in their community. He added that invasive vines can be a major nuisance in backyards by killing trees and overrunning lawns and gardens.

“As a society, we talk about the importance of preserving land, and yet we’re not really taking full advantage of the opportunity to grow trees there,” LeRoy said, “simply because we’re not managing vines – and it’s such a simple thing. The forest is a wonderful thing, and when we neglect it, it expresses itself as a tangle – not a forest.”

So, this spring why not cut down some invasive vines in your backyard or volunteer to help Friends of the Wissahickon to maintain and preserve our natural green spaces?