By: Tiffany Howard
The cold weather has begun to set in here in southeast Minnesota! The leaves have been changing colors and many plants are losing their leaves, which means it is time to cut and spray invasive species that stay green long after other plants have died off for the winter!
In addition to buckthorn which we have been feverously cutting because their ivy green leaves stick out like an eye sore, we have been searching for, GPSing, cutting and spraying the roots of invasive Oriental bittersweet (Celastrus orbiculatus). This plant is on the Minnesota Prohibited Noxious Weed list and is illegal to plant to sell or move to another location. Growing up I remember driving through the country and seeing roadside stands with farmers selling Oriental bittersweet as fall decoration because it looks really pretty, now I cringe at the thought.
Oriental bittersweet, also called Asian or Chinese bittersweet, is an invasive, introduced plant in the United States. It is a vine that grows up the trunk of trees, girdling them as they go up and eventually killing off the tree by removing the tree’s ability to transport water and nutrients upwards. There is such thing as a native bittersweet, it’s called American bittersweet (Celastrus scandens), these vines do not girdle trees but mostly just climb them to get to the top of the canopy. You can tell the difference between the two species, as least the female plants, by the color of their fruit capsule. The Oriental variety has a yellow fruit capsule while the American has an orange fruit capsule.
If you would like more information on Oriental bittersweet please check out the DNR website and if you think you have spotted Oriental bittersweet you can e-mail the “Arrest the Pest” program to report your sighting, in nature or on a roadside stand!