Oriental Bittersweet, Celastrus orbiculatus

Scientific Name: Celastrus orbiculatus
Common Name(s): Oriental bittersweet


Research Summary
: Sam J. 
My observations during my research were that it was amazing how many new facts there were to find, although it was a little bit challenging to find some of the facts. There were not very many resources; not nearly as many as I thought there would be at the beginning of the project.  I was surprised at some of the cool facts there were about Oriental bittersweet,  like how it spreads so quickly. I think that was the most important thing about this species that I learned and also how it grows so quickly and can be used as a medicine.

Identifying Characteristics
  • Alternate, 2-5  inches long, 1.4 to 2 in. wide.
  • Green, paler below.
  • Ooblong shaped fruits.
  • Red fruit with 3-4 small yellow orange leaves.
  • Plentiful with almost 370 on one vine.
  • Each capsule contains 1-2 seeds.
  • Stems are woody and twining and may reach 66 feet in length.
  • Roots are deep and spreading.


Taxonomy of Species
   Scientific Classification
 What That Classification Means
 Kingdom  Plantae  Eukaryotic, many celled, don't move, members make their own food,
 non-vascular and vascular. 
 Phylum  Magnoliophyta  Flowering plants that produce seeds.
 Class  Magnoliopsida
 Seed plants that produce an embryo with paired cotyledons and
 net-veined leaves.
 Order  Celastraes  Celastrales is an order of flowering plants. They are found throughout the
 tropics and sub tropics,with only a few species extending far into the
 temperate zone.
 Family  Celastraceae  Trees and shrubs and woody vines usually having bright-colored fruits.
 Genus  Celastrus  Genus of woody vines and erect shrubs (type genus of the Celastraceae)
 that is native chiefly to Asia and Australia: includes bittersweet.
 Species  Orbiculatus  Asian bittersweet, Asiatic bittersweet, Oriental bittersweet.
Similar species include:  American Bittersweet,  Asian Bittersweet,  Asiatic Bittersweet.

Location and Movement
Origin/ Native Range
 Asia (Korea, China, and Japan).
  • It was found in USA in 1860 and originally used for ornamental purposes and for erosion control.
  • It spread to Connecticut by 1916, Massachusetts by 1919, and New Hampshire by 1938.
Spread of Species
  • Spread by birds eating seeds and digesting them. 
  • Used for ornamental and/or growth for medicinal purposes and then the plants run out of control.
  • This plant can sprout through its own sprouts and berries.
Where is it now invasive?
  • All over northeastern and southeastern parts of the US extending to the southeastern edge of the Great Plains. 
  • This plant is invasive in its countries of origin.

Is this species in Maine?
Where has it been identified?
  • According to a University of Maine publication this species has been located in five counties in Maine. 
  • It has also been documented in Farmington, Maine and is probably located in many other undocumented regions in the state. Unable to find resources saying exactly where it is found. 
How was this species introduced?
 Most likely through seed dispersal or ornamental use. 

Natural Environment
  • Thrives in rain and sunlight but also survives in deep shade. 
  • Is found in distributed woodlands, thickets, fence rows, fields, along the coast, salt marshes, roadways, and railroads. 
  • It can tolerate a wide range of soil types. 
Climate and Temperature Range
  • Can tolerate a wide range of temperature and climatic conditions so that's why Maine and the other places are perfect, because they provide this type of climate.  
  • It likes the temperate zone which has temperatures ranging from 70 (F) to - 32 (F).

Ecological Interactions  Producer.
 It gets its nutrition from photosynthesis.
Consumed By  Many birds and small mammals eat the berries.

  • It kills many trees through its vines wrapping around and choking them.
  • Grows so thick on trees that it weighs them down and tears up their roots.  It can also grow so thick, it will block sunlight.
  • Can change the soil which can threaten native plants.
  • It has taken over an ecosystem when just one plant grows because it spreads so quickly.
  • Used as an Asian folk medicine for rheumatoid arthritis and the bark is used as a fine fiber in China.
  • Enzymes in the leaves clot milk - may possibly be used as a way to make cheese.
 Economic  Used by craftsmen to make decorative wreaths.

 Biological  No biological control methods.    
  • Integrated management including early detection and containment before spreading by using mowing and fire.
  • Frequent cutting and mowing helps cut down on population. Should be mowed and cut about every 2 weeks. 
  • Hand pulling but be sure to get all the roots.
  • It is used for medicine which helps minimize the numbers of plants.
  • It is sold in nurseries even though it shouldn't be, because when people buy it and plant it, the bittersweet will grow out of its growing space and take over the ecosystem.
  • People can prevent the spread by not buying or planting Oriental bittersweet.
  • Herbicides like triclopyr and glyphosate are applications to kill Oriental bittersweet. This works best when it is applied to freshly cut stems.
  • This can be done any time as long as temperatures are above 55 or 60 degrees Fahrenheit for several days.  There can't be any rain expected for at least 24 hours. 
  • It is likely that treatments will have to be repeated.

Interesting Facts *Oriental bittersweet can be used as a medicine.