Celastrus orbiculatus is a perennial deciduous, climbing, woody vine that can grow to lengths of 60 ft. (18.3 m) and up to 4 in. (10 cm) in diameter. The striated bark is brown to dark brown. The smooth glabrous twigs can range from light gray to dark brown in color.
Foliage
The alternate, elliptical to circular leaves are light green in color and 2-5 in. (5-13 cm) long.
Flowers
Small, inconspicuous, axillary, greenish-white flowers bloom from May to early June. Oriental bittersweet closely resembles American bittersweet (Celastrus scandens). The main difference: Celastrus scandens has flowers and fruits at the ends of branches; Celastrus orbiculatus has flowers in the axils of the leaves.
Fruit
The small globose fruits are green when young; ripen to yellow; then split to reveal showy, scarlet berries that persist into winter.
Ecological Threat
Celastrus orbiculatus is commonly found in old home sites, fields, and road edges. The fast growing vines can cover, shade and outcompete other vegetation. It can even girdle and kill large trees. Birds and other wildlife eat the fruit, thus distributing the seeds. It hybridizes with Celastrus scandens, potentially leading to loss of genetic identity for the native species. It was introduced from China around 1860 as an ornamental.