ORIENTAL BITTERSWEET AKA Celastrus orbiculatus 

Welcome to the Scotland Invasive Plants Working Group.  If you have some time today, click on some of the other informative links. Thank you for your interest in eliminating invasive Oriental Bittersweet from our town land and your own land. 

A native of Japan, Celastrus orbiculatus was brought to the United States as seeds in 1879 by Samuel Parsons who it is believed purchased seeds from Thomas Hogg Jr who was living and working in Japan, and whose father had a horticulture business in New York. The seeds were grown at the Arnold Arboretum outside of Boston, MA. After about ten years, the plants were offered for sale by Samuel Parsons who operated Kissena Nurseries in New York. The plant appears in one of their nursery catalogs from the 1880's, where it was described as very decorative especially during the winter months with its colorful display of yellow and orange seeds extending along the entire vine.  Although it remains a very decorative vine today, its colorful and prolific yellow capsules with their orange seed containing fruits have scattered over the years and have grown into the tangled vining plants that appear just about everywhere in our landscape. At this point our fields and forest edges have become incredibly overgrown with Asian bittersweet. Its vines have climbed into the treetops killing trees by wrapping around them tightly and girdling them or with their weight downing tree branches and even toppling older growth trees.  As more Bittersweet seeds fall new plants sprout and continue forming an increasingly impenetrable tangle that shades out native plants. The reward for removal of this plant is allowing native species to return to the landscape and protecting trees at the woodland's edge. You will also realize improved esthetics given the ability to see more clearly into a woodland unencumbered with a tangled mass of invasive vines.  This will also allow for easier access for recreational activities.

HOW TO REMOVE

The good news is that with a bit of persistence, this plant is fairly easy to control.  Bittersweet can actually be eliminated from areas where it has become troublesome.  It is a matter of cutting the trunk portion of the bittersweet back repeatedly while also cutting the "tree ladder". The tree ladder being the lower branches on any trees growing near the vine that make it possible for the vine to climb into the tree canopy.  Though it can be done any time of year, it is sometimes easiest to begin the process during the winter months when the vine is most easily accessible. At this point cut the trunk of the vine and any surrounding lower tree branches.  There is no need to physically pull the vine from the tree branches.  In fact, doing so could damage the tree. The upper portion of the vine will die back and disintegrate surprisingly quickly once its connection to the roots has been severed.  If you can pull out the root after cutting the vine, that will be helpful in the plant's faster demise.  Repeating the process of cutting the bittersweet as it attempts regrowth several times during the summer months will continue to sap the plants strength.  Your persistence will eventually kill it.  If you want to ensure that this pant does not regrow from the cut stumps simply paint them with a concentrated application of herbicide.  Eventually you will be left with only young Bittersweet plants sprouting from fallen seeds, and these will be quite easy to pull out by the roots.  They have a bright orange root system easily recognized.  I often hang the young plants I remove in the branches of a nearby shrub where they will they dry out and lose their vitality.  Of course you can also collect them, bag them up and dispose of them in the landfill. 

This invasive plant has no natural predators, so it is up to us to keep it contained within our landscape!