Wild cucumbers (Echinocystis lobata) are in full force this time of year. They are found in moist, rich soil in areas such as woodland edges, landscapes and thickets. These plants are aggressive and can smother trees. Characteristics include bright green plants creeping or climbing to 25’, twining stems often grooved and angled, leaves that are maple leaf-shaped and sandpapery with a heart-shaped base, their long, curly, branched tendril is opposite the leaf; and the flowers are white to greenish yellow or yellowish green. The fruit is covered with sharp spines and contains a few seeds.
To remove these plants earlier in the year, hand remove or dig seedlings until small plant stage (less than two feet in length). At their current stage, pull or cut the larger plant stems near ground level (and before flowering, ideally); take similar action if regrowth from roots occurs. Pulling the plants at any time is always a good idea, especially before the pods open.
Herbicides should only be used before vines begin climbing up and over other desirable plants; even at that, extreme care should be taken not to get any herbicides on nearby desirable plants.
More information may be found at https://apps.extension.umn.edu/garden/diagnose/weed/broadleaf/vining/wildcucumber.html.