MOBILE, Ala. - If a gypsy moth attacks a tree, Auburn University entomology professor Wayne Brewer won't be far behind it, checking his traps.
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Brewer attempts to keep track of gypsy moths that sometimes hitchhike into Alabama on campers, mobile homes and railroad cars arriving from northern states where the insects are more common.
The moth lays its eggs on vertical objects, not just trees, Brewer said Friday.
"The real problem is human beings transporting eggs accidentally. I've been conducting the surveys for several years. We find a few moths every year," said Brewer.
Fortunately, the moths have not been able to establish reproductive colonies in the state, he said.
The immature stage of the moth devours leaves and, if not eradicated, will kill a healthy tree. Gypsy moth caterpillars feed on leaves of more than 500 types of trees and shrubs.
Brewer and his aides have set out traps in 45 of the state's 67 counties, checking them for moths.
Now he's tracking another threat - an exotic beetle, not yet spotted in Alabama - that's killing trees by the thousands elsewhere. Brewer is searching for the emerald ash borer, a small but beautiful beetle, which has devastated ash stands in Michigan, Indiana and Ohio.
Brewer appealed for the public's help in reporting any ash trees in Alabama that show symptoms of a borer attack. He said they should be reported to him at Auburn University.
"Generally, what you would see is the tree looking like it's in need of water," he said.
Tree owners also can look for a tiny D-shaped exit hole left by emerging adult beetles on the branches and trunks of ash trees. The borer girdles the tree. Infested trees often lose 30 to 50 percent of their canopy in only one year and die within three years of infestation.
Ash trees in Alabama are commonly found along river bottoms and other wet areas.
"We have some in yards," Brewer said. Some grow on the Auburn University campus.
Early detection of the borer could save a property owner major losses from landscape damage.
Brewer, professor in the Department of Entomology and Plant Pathology and an Alabama Cooperative Extension System entomologist, has a grant from the U.S. Department of Agriculture's Animal and Plant Health Inspection Service to survey for signs of the emerald ash borer.
A native of China, the ash borer can easily fit on the surface of a penny. It was first identified feeding on ash trees in southeastern Michigan in 2002, but had eluded detection for as long as five years.
Forestry officials now are taking major steps to combat the borer, particularly in Michigan, which has an estimated 700 million ash trees.
"Michigan already is spending hundreds of thousands of dollars to prevent the further spread of these beetles, and Alabama undoubtedly would be saddled with similar costs if the pest became established here," Brewer said.
Unfortunately, the technology used to monitor for gypsy moths doesn't work with borers.
"There are no traps, no attractants and no pheromone (excretions)," he said. "About all you can do is examine ash trees for symptoms of infestation. Since it takes a while for evidence of this infestation to show up in trees, there is the chance you'll miss some initially."