The Berries of Oriental Bittersweet

Oriental bittersweet produces bright orange berries enclosed in yellow husks that split open in the fall. Because the colorful vines are often used in decorative wreaths and crafts, the berries have been widely spread beyond their original planting areas.

These berries are a key reason the invasive vine spreads so aggressively, as birds eat the fruit and disperse the seeds across forests, yards, and roadsides, and as people take the vines elsewhere for decorative purposes, the seeds are spread throughout Massachusetts, New England and beyond.

Oriental Bittersweet vs. American Bittersweet

While Oriental bittersweet is an aggressive invasive plant in Massachusetts, there is also a native species of bittersweet known as American bittersweet. The two vines look similar, but several characteristics help distinguish them.

Berry Location:

• • Oriental bittersweet produces orange berries with yellow husks along the entire length of the vine at the leaf joints.  

  • American bittersweet produces berries only at the ends of branches.

Leaf Shape:

• • On mature growth, Oriental bittersweet typically has rounder, broader leaves.

  • American bittersweet has more elongated leaves that taper toward the tip.

  • However, on new growth of Oriental bittersweet, leaves can appear more elongated and tapered toward the tip though smaller then American bittersweet. The best way to tell the difference is the placement of the berries.

Growth Habit:

• • Oriental bittersweet grows very aggressively, climbing trees and overtaking surrounding vegetation.

  • American bittersweet grows more moderately and typically does not overwhelm nearby plants.

Impact on Trees:

• • Oriental bittersweet can strangle trees, weigh down branches, and contribute to tree failure.

  • American bittersweet rarely causes structural damage to trees.

Presence in Massachusetts:

• • Oriental bittersweet is very common and widely invasive throughout Massachusetts.

  • American bittersweet is native but now relatively uncommon in many areas due to competition from the invasive Oriental bittersweet.

Why Root-Level Treatment Matters

Many invasive species spread through underground rhizomes or root systems. Cutting, smothering or mowing alone rarely eliminates the problem and requires labor intensive strategies. Mechanical removal (digging up the plant or pulling it by hand) typically leaves behind root fragments that can regrow into infestations.

Effective management requires treatment that reaches and destroys the plant’s root structure.

Proper identification, timing, and application method are critical to achieving long-term control while minimizing environmental impact.