When I visit family in Tennessee, the first thing I notice is always how much greener it is than Colorado, even in winter. Drive any stretch of highway from the middle to eastern portion of the state, and you’ll be greeted by mile after mile of greenery on all sides. Take a closer look however, and you’ll realize that not all of that foliage is friendly.
Much of it is kudzu, a Japanese plant introduced in the United States in 1876 at the Philadelphia Centennial Exposition, according to the United States Forest Service. It arrived in the lower portion of the U.S. soon after, and was used as an ornamental vine and erosion control crop.
But what was once a benign decoration has now become an invasive species. Kudzu went wild, literally, in the moist, temperate climate and eventually came to be known as “the vine that ate the South.” The plant itself is bad enough, growing so voraciously that it chokes out the light and kills everything else in sight, but now scientists have discovered that the vine is crawling with a new threat: kudzu bugs.
Scientifically known as Megacopta cribraria, the kudzu bug is not a beetle like most people think. More closely related to the stink bug, this insect won’t be winning a beauty contest any time soon. Just like the plant they live on, kudzu are native to Asia, and were first detected in the U.S. in Georgia in 2009. They have since expanded their territory as far north as Virginia. The bugs have an interesting life cycle: the first generation, which hatches in the Spring, usually never leaves the kudzu where it was born. This was thought to be a limiting factor on how far they can spread, but new research shows that may no longer be the case.
Kudzu bugs, even first generation hatchlings, have learned how to exist without the safety and nourishment of the kudzu plant, which means areas usually safe are now threatened by its voracious appetite.
Under controlled conditions in a greenhouse laboratory, researchers at North Carolina State found that immature Generation A kudzu bugs were not limited to feeding on kudzu – they were able to feed exclusively on soybeans, reach maturity and reproduce.
“Researchers began seeing some of this behavior in the wild in 2012 and, while those data aren’t quite ready for publication, our lab work and the field observations indicate that kudzu bugs are potentially capable of spreading into any part of the U.S. where soybeans are grown. And soybeans are grown almost everywhere,” says Dr. Dominic Reisig, an assistant professor of entomology at NC State and co-author of a paper on the research. “It also means that both annual generations of kudzu bugs could attack soybean crops in areas where the bug is already established, which would double the impact on farmers.”
This threat is likely to make pesticide peddlers like Monsanto see dollar signs for days, but there are better ways to control and even eliminate kudzu bug invasions. Back home in Tennessee they’re using goats to reduce kudzu growth and thus eliminate the kudzu bug’s favorite breeding ground. Other remedies include window traps (they’re attracted to light), cinnamon and (blech) hand removal in the morning or when it’s raining.