Oriental Bittersweet
Celastrus orbiculatusCelastraceae
Whole Plant
Flower
Fruit
Fruit
Whole PlantFlowerFruitFruit
Fruit
Fruit
Leaf
Stem
FruitFruitLeafStem
Habitat
Habitat
HabitatHabitat
Photos (c) Cheryl Comeau Beaton unless otherwise noted

Synonyms:

  • Asiatic bittersweet, Round-leaved bittersweet
  • Celastrus articulatus

The Plant:

  • A deciduous, woody perennial. Grows as a vine or sometimes as a trailing shrub.

The Leaves:

  • glossy
  • alternate
  • radiate around the stem
  • light green
  • finely toothed
  • ovate to obovate

The Stem:

  • up to 4 inches in diameter
  • round with brown striated bark
  • smooth and glabrous twigs
  • dark brown or light gray

The Flowers:

  • Small (.07 to .15 inches long, .1 to .2 inches wide) greenish five-petaled flowers held in leaf axils. Blooms from May to early June.

The Fruits:

  • green maturing to yellow, orange then tan
  • splits open in winter
  • dried, tan covering folds upwards
  • reveals 3 red fleshy sections (arils)
  • containing 2 white seeds

The Habitat:

  • very successful in the shade
  • salt marsh edges, coastal areas
  • early successional fields, woods
  • roadsides, railroad tracks
  • hedgerows and forest edges

Dispersal:

  • birds
  • small mammals
  • float in water
  • yard waste
  • also reproduces vegetatively by root suckers

Key ID Features:

  • vine
  • alternate leaves
  • flowers in leaf axils
  • yellow fruits open to reveal red, fleshy arils
  • round brown stems
  • orange taproot

Similar Species:

  • American bittersweet (Celastrus scandens): A native species that looks similar, but develops fruits only at the ends of stems, not in leaf axils as with Oriental bittersweet. Contrast between arils and ovary walls is not as strong as with Oriental bittersweet.
  • There is a hybrid between C. scandens and C. orbiculatus that can be difficult to distinguish.

Notes:

  • Asiatic bittersweet is a threat to native vegetation due to its rapid growth rate, the ability to send up shoots from roots (root suckering), and high reproductive rates allows for dense and quick growth. This climbing vine shades out native vegetation and can kill large trees by constricting or girdling stems or by adding weight to limbs causing them to break. Oriental or Asiatic Bittersweet is often confused with native American Bittersweet (C. scandens), which flowers at the tips rather than in the leaf axils. Improper disposal after use in floral arrangements contributes to the spread of Asiatic Bittersweet.

Growth Form: Vine

Origin: East Asia, Japan, Korea, China

Level of Invasiveness for Nantucket: Invasive

Level of Invasiveness for Massachusetts: Invasive

Massachusetts Cultivation Restrictions: importation ban, propagation ban




Credits: The Electronic Field Guide to the Invasive Plants of Nantucket (c) 2005-2006 Maria Mitchell Association, EFG Project, UMass Boston