Cut the vines as close to the root collar as possible with a coarsely toothed saw. Start cutting the vines at the start of the growing season, and repeat cutting every two weeks until the end of it. Mow weekly to cut down any small shoots. Removing vines helps relieve strangled plants and deplete Oriental bittersweet's root stock and seed production.
Remove Oriental bittersweet's entire root system with a digging tool, such as a pulaski. If any part of the root system is left behind, it may resprout.
Collect fruit and removed plant parts, and place them in a black plastic bag for disposal.
Wear protective eye gear, a long-sleeved shirt, pants, socks, chemical-resistant footwear and gloves. Keep in mind that herbicides are harmful if ingested, inhaled or absorbed through the skin, and avoid contact with skin or breathing in vapors.
Spray small, young vines with a 2 percent solution of triclopyr, meaning 8 ounces of triclopyr per 3 gallons of water, during the growing season. Treat the vines when there is no chance of rain for the day and the temperature is above 45 degrees Fahrenheit. Coat the foliage of the vines completely, but not so that it drips off. Repeat treatments every two weeks.
Cut large vines about 2 inches above ground level in the spring or summer. Paint the Oriental bittersweet's cut end using a paintbrush saturated with a 25 percent solution of triclopyr. Continue making applications every two weeks until the Oriental bittersweet dies back.