Q: I’ve noticed a lot of vines in trees around the area this year, and they're not woodbine. It appears they smother the trees. What are they? What’s an effective way to get rid of them? I feel we need to communicate they are a hazard to the communities.
A: To answer this question, the Herald reached out to Don Kinzler, North Dakota State University Extension, Cass County Horticulture, who also writes a weekly column on gardening that regularly appears in the Herald.
Here is his answer:
There are three main vines that we might find aggressively climbing into trees in our region. One is grape vine, which has a rounded leaf with jagged, toothed margins. The second is parthenocissus, which is a genus of vines with five leaflets arranged in a hand-like formation. Within the parthenocissus group are Virginia creeper, Engelmann ivy and woodbine, which you mentioned. It sounds like you're familiar with woodbine, so we can probably rule that out.
That brings us to the third possibility, which is the most likely: wild cucumber. Wild cucumber is an interesting vine that can completely crawl over existing trees and shrubs, completely obliterating them from view. It's an annual vine, meaning it starts from a seed each spring, grows to a height that can reach 30 feet in one growing season, and then dies during fall frost. It produces plentiful seed, which bursts from the seedpods that look like little rounded cucumbers. It's these seeds from which future wild cucumber vines grow. The root of the vine does not survive winter.
The leaves of wild cucumber are light green, and have five lobes, in a star-shaped pattern. Greenish-white flowers arise in early summer, eventually followed by the light green cucumber-like pods. The vine grows rapidly from seedlings that arise in spring. Wild cucumber vines are most commonly seen along riverbank properties or in lakes country, in native stands of trees.
To control wild cucumber, herbicide sprays are usually not workable, because it's difficult to spray the vine without harming the plant on which the vine is clinging. The best method is to break the cycle of seed production, by not allowing the vine to produce its fruit. When the vine is first noticed, locate the base, and cut the stem or pull the roots. This can be done anytime through the season, as long as you destroy the vine before fruit formation. Seed from past years might still be present in surrounding soil, but by vigilantly not allowing the vines to regenerate through fruit and seed, it will dwindle out.
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