The idea to introduce Japanese honeysuckle into the United States in the middle of the 19th century proved to be a bad one. Originally brought over from Japan to be an agent to control erosion, it did so well that it turned into an invasive species. It grows so lush, though, that its shade began to prevent other native plants from thriving.
Spreading through seed dispersal via birds and through a series of underground roots called rhizomes, Japanese honeysuckle can form dense areas on your property. You can control it best with either manual labor or chemical means.
Recognizing Japanese honeysuckle is the first step in eradicating it. Japanese honeysuckle is evergreen in the warmer climates it grows in, such as the Deep South. In other places where the weather turns significantly colder, it still holds its leaves until late into the winter.
Japanese honeysuckle will twist around any upright structure, often covering taller shrubs and trees when growing on the borders of your property. The woody tan vine can reach lengths of 80 feet in extreme instances and it is typically about 2 inches thick. The leaves grow opposite each other in pairs on the stem and have an elliptical shape.
The flowers, which occur from April into the middle of summer, have a pleasing scent and are white to dull yellow in color. They are tubular and eventually turn into shiny black berries.
When you find a small amount of Japanese honeysuckle, you may kill it by pulling it up using your hands. You have to get both the vine, which is above the ground, and the root system below the earth. The best results occur when the soil is somewhat damp and loose, allowing you to reach down low on the vine and pull it up, with the roots coming with it. However, maintain close vigilance on the spot where you pulled the honeysuckle from to see if any new growth has occurred.
Often you will find Japanese honeysuckle twirled completely around a tree or a shrub. This can eventually kill the host plant and requires you to resort to mechanical methods of control. You can cut them in half and pull them off by yourself or employ the help of someone with a chain saw.
The Plant Conservation Alliance Alien Plant Working Group recommends using a rake to lift the vine so the chain saw has clearance to buzz through the stems as close to the ground as possible. The roots still are a factor and you can get them out with a digging tool.
You can use one of Japanese honeysuckle’s traits against it when it completely entangles with other plants. The ability of the leaves to last long past the point when other shrubs and trees are dormant means you can spray it with a herbicide containing the chemical agent glyphosate.
Use a sprayer in the latter part of autumn and apply a 5 percent to 8 percent solution to the leaves to kill the plant. You can also apply this type of herbicide to any stems that you cut and any new sprouts that you discover at any time of the year when the ground is still unfrozen.