Oriental bittersweet is quickly invading my landscape beds. This plant seems to grow everywhere and spreads very quickly. Although it has beautiful orange fall fruit, birds and other animals disperse the seeds to other locations. In my case, I have this aggressive vine growing throughout my vinca groundcover, tangled within my honeysuckle and lilac bushes, and lurking among various other flower beds.
By definition, invasive plants are alien or "exotic," meaning that they were introduced into an environmental where they do not natural occur. Additionally, the invasive plants aggressively compete with native species and other ornamental landscape plants. They are often able to choke out other plants due to their very strong, rapid growth patterns and reproduction methods.
Oriental bittersweet has all these aggressive characteristics. It grows quickly and strong in many growing conditions. It is spread by seed to new areas. Once established, the plant also spreads quickly through underground root structures that send up new plants throughout the landscape.
Don't dismay if you like using bittersweet in holiday decorations because there is a good alternative. Our native American bittersweet is not as troublesome. Candice Miller, University of Illinois Extension educator in horticulture, describes the differences between our native American bittersweet from the invasive Oriental Bittersweet in her Hort in the Home Landscape Blog found at http://web.extension.illinois.edu/jsw. She says to look at the seed capsules and berry placement.
Oriental bittersweet has yellow seed capsules on red berries (Give a yell when you see yellow!) whereas American bittersweet has orange seed capsules on red berries (Orange is OK!). Oriental bittersweet has berries strung-out along the stem (Strung-out is bad!) while American bittersweet's berries are all clustered near the end (Saving the best for last!). Miller's blog includes a link to a factsheet from University of Minnesota Extension on oriental bittersweet.
The first step in controlling invasive plants is proper identification. Often you cannot simply pull or mow invasive plants to control them. The easiest and least expensive time to control or manage invasive weeds is when plants are small – usually in the spring. Because invasive plants are hardy and persistent, they can be difficult to control once established. I used a combination of digging out the roots and applying a cut surface herbicide application to control my bittersweet problem.
Please help stop the spread of invasive plants by choosing landscape plants wisely.