Oriental Bittersweet (Celastrus orbiculatus)
Appearance: Deciduous vine that grows up to 66 ft. long. Vines climb by winding around a tree or other support structure.
Leaves: Alternate, simple, vary in shape from oblong to almost round. Leaf size is also variable from 2-5" long to 1.4-2" wide. Leaf margins have rounded teeth.
Flowers: There are separate male and female plants. Flowering occurs in the spring and flowers are arranged in clusters of 2-7 at the leaf axils. Each flower has 5 petals and 5 sepals. Flowers are small and greenish-yellow.
Fruit: Fruits are round and change in color from green to bright red with a yellow capsule as they mature. Typical female plants can produce up to 370 fruits which ripen in the fall.
Roots: Underground rhizomes spread and can send up new plants.
To distinguish from the native vine, American bittersweet (Celastrus scandens):
- American bittersweet has orange capsules around red fruits, Oriental bittersweet has yellow capsules around red fruits.
- American bittersweet flowers and fruits are only found at the terminal ends of stems, Oriental bittersweet flowers and fruits are found all along the stem at leaf axils.
- Leaf shape is highly variable and not a good characteristic for distinguishing American vs. Oriental bittersweet.
- See MDA website for photos comparing the two species.
- Additional resources for distinguishing American and Oriental bittersweet:
- American (climbing) bittersweet (Celastrus scandens) and its cultivars
- MDA Oriental bittersweet early detection
- What do the Holidays and Invasive Species have in common? Oriental bittersweet
- MDA Oriental bittersweet fact page
- Minnesota Noxious Weeds (MN DOT)
- USDA Forest Service Oriental bittersweet information
- USDA Forest Service Oriental bittersweet fact sheet
- Plant Conservation Alliance
- Hawykeye CWMA Oriental bittersweet brochure
- URI CELS Outreach Center Oriental Bittersweet Control Fact Sheet
- Midwest Invasive Plant Network Asian (Oriental) Bittersweet fact sheet
- NRCS Oriental bittersweet Management