This month’s species spotlight is the Japanese honeysuckle. It was first introduced to the United States via Long Island in 1806 from Asia. Far from its home in Japan and Korea, it was widely planted as an ornamental and states long promoted it for erosion control and wildlife habitat. Now, the woody vine is considered invasive in 26 states of the eastern United States.
You can find Japanese honeysuckle (Lonicera japonica) in disturbed areas, forest openings, roadsides, field edges, and floodplains. It creates thick carpets on the ground through rhizomes and grows by aboveground runners that girdle and smother shrubs and trees. Honeysuckle prefers full sun and well-drained soils, but will also tolerate partial shade and drought. In late spring, it produces pinkish-white flowers which fade into yellow. In the fall, the plant produces black-colored berries containing its seeds which are eaten and spread by birds. In warmer climates, the honeysuckle remains evergreen, but in the Triangle, winter temperatures cause the oblong leaves to die back. Even in winter, Japanese honeysuckle can be easily distinguished from native honeysuckles by its brittle, hollow stems with bark that easily peels off.
Removing Japanese honeysuckle
Ground spreading Japanese honeysuckle can be controlled by hand pulling, but it is essential to completely remove the roots to prevent regrowth. Remove, dry out, and dispose of the vines to prevent resprouting. Vines smothering a plant should be cut at the root and carefully removed. If the cut stump cannot be easily removed, a glyphosate herbicide can be painted on to kill the root system.
Japanese honeysuckle foliage remains late into fall when many other species have already lost their leaves. This is advantageous for applying a glyphosate foliar spray as it will not harm any non-target species. Once applying the foliar spray, the honeysuckle should not be removed for a whole growing season to allow the plant to absorb the herbicide.
Many nurseries still sell Japanese honeysuckle under the cultivar “Hall’s honeysuckle” despite its invasive nature. Beautiful vining native alternatives to Japanese honeysuckle include coral honeysuckle (Lonicera sempervirens), crossvine (Bignonia capreolata), and Carolina Jessamine (Gelsemium sempervirens).
Creative Control: Japanese honeysuckle jelly
You may recognize Japanese honeysuckle as the species you harvested as a child for its honey-like taste. Although its berries are poisonous, its yellow flowers can be picked and added to salads and drinks. You can even make Japanese honeysuckle jelly which tastes and smells like its sweet nectar. It is simple, just be sure to follow proper canning protocol.