Invasive Bittersweet

Appearance

Invasive bittersweet (Celastrus orbiculatus), is a woody, deciduous vine that can grow up to 100 feet in length. It features round, glossy leaves with serrated edges, typically arranged alternately along its stems. The plant produces small greenish-yellow flowers in the spring, which later develop into bright yellow seed capsules. When these capsules split open in the fall, they reveal a vivid orange-red berries, which persist through the winter and are a key identifier in being able to identify invasive bittersweet versus American bittersweet.

Habitat and Spread

This invasive thrives in a variety of environments, including forests, grasslands, roadsides, and urban areas. It prefers well-drained soils but it highly adaptable and can grow in both sunny and shaded conditions. The plant spreads primarily through its berries, which are consumed by birds and other wildlife that disperse the seeds. Additionally, it can propagate through its extensive root system and shoot up from the underground rhizomes.

Impacts

Invasive bittersweet poses significant ecological threats. Its aggressive growth can smother and outcompete native vegetation, including trees, shrubs, and herbaceous plants. The vine climbs and wraps around trees, constricting growth and sometimes causing structural damage or even death. This process, known as girdling, can topple trees during storms, further disrupting ecosystems. Additionally, the dense thickets formed by bittersweet reduce biodiversity by crowding out native plants and altering habitats for wildlife.

Control and Management

1. Mechanical Removal: Hand-pulling young plants or cutting mature vines close to the ground can help reduce its presence. Ensure that all roots are removed to prevent regrowth.
2. Chemical Control: Herbicides, such as glyphosate or triclopyr, can be applied to freshly cut stumps or foliage. Follow all label instructions to minimize environmental impact.
3. Integrated Approach: Combining cutting with subsequent herbicide application often yields the best results. Repeated treatments may be necessary to control regrowth.

Prevention and Awareness

• To this day, dried flower arrangements and wreaths can contain this plant, so be aware and avoid accidentally spreading its seeds.
• If you would like to plant bittersweet try planting the American Bittersweet
  • How can you tell the difference between American and Invasive Bittersweet?
    • American Bittersweet has smooth stems and oblong leaves.
    • The berries appear on the tips of the vines only, while those of invasive bittersweet have berries that grow along the vine.