By Stan Maddux
NASHVILLE, Tenn. – Tennessee State University is leading the charge to find better ways of combating a beetle deadly to trees, including those producing nuts and fruit.
TSU has received a $6 million grant from the USDA’s National Institute of Food and Agriculture to develop new tools for managing the flat headed borer, which attacks trees in nursery, landscape, nut and fruit orchard systems. Researchers at universities across the nation are part of the four-year federally funded effort.
“These borers cause serious damage to the nursery industry and sometimes a single borer can kill or severely weaken a small tree,” said Dr. Chandra Reddy, dean of TSU’s College of Agriculture.
According to researchers, the flat headed borer is becoming a problem in Tennessee and other states like Florida, Texas, California and Oregon. Twenty seven researchers, including three from TSU, will also try to determine how prevalent the tree killing invader might be in other states like North Carolina, Georgia and Alabama.
The research could also make a positive impact on controlling the pest worldwide since the flat headed borer exists in other continents.
“This beetle attacks trees everywhere. Current climate issues are causing them to be more problematic,” said Dr. Karla Addresso, associate professor of entomology at TSU and director of the project.
According to researchers, other goals include identifying what makes trees susceptible to attack, determining how effective insecticides entering the market are in fighting the beetle and calculating the cost benefit of effective pest management strategies.
“More environmentally friendly biological options like entomopathogenic nematodes have not been investigated at all with this borer group and that is one aspect of this project,” said Jason Oliver, a TSU entomology professor and co-director of the project.
According to researchers, young trees are more prone to attack by the beetle which has other species like the Pacific Flatheaded Borer impacting young and mature fruit and walnut trees in places like California and Oregon. Other varieties include the Appletree borer which has taken a liking especially for apple and maple trees primarily in the eastern states, according to researchers.
Mark Longstroth, a fruit educator at Michigan State University, said the flat headed borer hasn’t been a much of an issue in his state, but it appears to be related to the Emerald Ash Borer responsible for killing a large number of Ash trees in the state.
He said the flat headed beetle chews the area between the bark and the wood after digging into a tree.
“They’re eating the layer cells that transport the sugars and make new wood and bark. Essentially, what they’re doing is killing the living part of the tree,” Longstroth said.
He said there have been problems in Michigan, though, with the Black Stem Borer attracted mostly to young trees weak or stressed by drought and harsh winters.
Young apple trees planted closely together in high density are also susceptible to attack by the Black Stem Borer.
Longstroth said holes left in the bark by the Black Stem Borer allow fungal disease to enter and symptoms are not usually noticeable until it’s too late to save the infected trees.
“You don’t really notice anything wrong with the tree until it seems sick,” he said.