If you’re looking up toward the sky at Lake Murray this summer, there may be a chance you can catch one of South Carolina’s most incredible natural phenomena. Every Summer,...
Everything You Need To Know About Kudzu and the Kudzu Bug
The Kudzu Bug, Megacopta cribraria, is an invasive species that was first detected in North America in 2009. The species feeds on legumes. Kudzu and soybeans are preferred legume hosts. When the species feeds on Kudzu, it is beneficial, as it was determined that the insect could stall biomass of Kudzu growth by 30%. When the species feeds on soybeans, it is an economic pest, as significant infestations can cause yield losses up to and sometimes exceeding 60%. SCETV interviewed Clemson University’s Professor of Entomology, Jeremy Greene, at Clemson’s Edisto Research and Education Center in Blackville, S.C. last week for more information.
The Kudzu plant was introduced to the United States to control erosion in the late 19th century. Unfortunately, it got out of hand and it is now referred to as the “vine that ate the South”. During the Summer months in South Carolina, Kudzu can grow a foot a day.
The Kudzu Bug species is truly invasive as well, most likely originating from Japan or China, based on genetic evidence. A likely scenario is that one gravid female made it on board an international flight from the Far East straight to the U.S.A. (most likely Atlanta, Georgia), got out of the airplane in Atlanta, and started colonizing patches of Kudzu east of the Atlanta area. There were 9 counties in northeast Georgia that had confirmed findings of Kudzu Bug in 2009. By 2010, South Carolina had the insect in 16 counties. By May of 2011, South Carolina became the first state to be totally infested with the species. Now, the species covers the entire southeastern U.S.A.
Kudzu Bug also “likes” light colors, such as the white trim used on houses, and it congregates on homes and is a tremendous nuisance pest.
Dr. Jeremy Greene and his colleague Dr. Francis Reay-Jones worked with a couple of graduate students on the Kudzu Bug as it related to soybean production. They generated more than a dozen scientific papers on the pest in soybeans. Kudzu Bugs wreaked havoc on soybean producers and home owners for years, primarily between 2010 and 2015. Then, they began to notice a sudden decline in their numbers.
One of the things they discovered is that a naturally occurring fungal organism that lives in our soil infects the Kudzu Bug. This entomopathogen called Beauveria bassiana attacks insects, but a strain was selected that recognized Kudzu Bugs so well, it actually caused a significant decline in numbers of the species. There is also a small wasp that specifically attacks the eggs of the Kudzu Bug. Both of these natural enemies have exerted tremendous biological control on the Kudzu Bugs.
Dr. Greene says, “I think that the fungal pathogen has done most of the harm to Kudzu Bug.” So, this would likely explain the perception of Kudzu being “knocked back” some during the years when we had significant populations of Kudzu Bugs that were feeding on Kudzu, and why the invasive vine weed seems to have been released from the natural control of Kudzu Bug in recent years. However, Kudzu is unfortunately here to stay.