The other day a Monarch butterfly stopped to rest on the wild grape vine which covers the chain link fence which surrounds my in-ground pool. I think that was the first time I’ve ever seen a butterfly alight on the grapevine, so it got me thinking. Do wild grapes support pollinators?
Wild Grapes support pollinators
Yes! According to my research, wild grape flowers are frequented by native bees and wasps, most notably the small sweat bees. They also are a source of food for songbirds, gamebirds and small and large mammals. I also found they were dioecious, which means they require insect cross-pollination, requiring both male and female plants to be able to produce fruit.
However, grape vines are invasive
Native wild grape species grow in a variety of habitats from dry, sandy soils to rich, moist soils throughout the United States. Using their tendrils for support, they like to climb and intertwine in upright structures, including trees and shrubs. Although they can co-habitat with most trees and shrubs, left uncontrolled, they can deform a tree by shading out new branch growth and breaking branches from the added weight and from girdling. They can be absolutely deadly, if left to overtake a tree canopy. They block out light, reducing the photosynthesis and weakening the tree. They can form a platform in the tree canopy which holds the weight of snow and ice, causing a weakened tree to break or even topple.
Native wild grapes have small almost green flowers, barely visible to the human eye because they lie hidden under fast-growing leaves. In late summer to early fall their dark purplish-black berries appear and are immediately picked off by the birds and mammals. They propagate from seed or sucker from previously cut vine stumps, but they must have full sunlight. They do not thrive in the shade. The seeds spread by birds or mammals remain viable for many years, so given the right conditions, they can appear almost anywhere. Left without control, the vines can reach up to 50 feet (15 meters) and have many vines radiating out from one root ball.
Controlling grape vines
There are several ways to control wild grape vines. I don’t recommend simply cutting them down, because they will grow back more vigorously than before. If you are averse to using herbicide, you can smother the stem end after cutting it from the rest of the vine. Or, you can dig the root out of the ground after having cut the stem at the end. Or you can cut the stem just above the ground and safely and carefully paint the cut end with herbicide. Any of these methods will work for vines growing up into trees and shrubs.
According to the Cooperative Extension, “the easiest way to handle them is to cut them down at the base and IMMEDIATELY treat the freshly cut stump with an herbicide with glyphosate or triclopyr. Do not let the herbicide get on the trunks of your trees (or anything but the vine).” (Cooperative Extension)
When using herbicide, I prefer to cut the vines in the fall and safely and carefully paint the the cut end of the stems. I’ve found for most woody-type stem plants, cutting in fall when they’re starting to go dormant and painting just the cut stem with herbicide is the most effective. Although tempting, cutting and painting during the summer when you first spy the plant, typically results in regrowth and suckering the following year, if not the same year.
So, all in all, I feel we should think of grapes and grape vines as friend in our landscape because they support wildlife. But just like with some friends we all have, we need to take great care with how we let that friendship affect us.