News and Public Affairs

That somebody happens to be Dr. Wayne Brewer, an Alabama Cooperative Extension System entomologist and Auburn University professor of entomology who, for several years, has been monitoring much of the state for signs of the gypsy moth, a devastating forest pest that has wreaked havoc in other regions of the country.

Recently, his job became more challenging after he obtained a grant from the USDA’s Animal and Plant Health Inspection Service to survey for signs of the emerald ash borer.

He doesn’t seem to mind the extra work, though. Having seen the damage these beetles have caused in other parts of the country, he is a firm believer in the old maxim that an ounce of prevention is worth a pound of cure.

By every measure, the emerald ash borer is a pest worth watching --- and preventing. A native of China, the beetle can easily fit on the surface of a penny. It was first identified feeding on ash trees in southeastern Michigan in 2002. Experts believe it had eluded detection for as long as five years --- not surprising considering the symptoms often pass unnoticed. The borer also has been detected in Windsor, Ontario; Maryland; and a small section of northwest Ohio.

The most obvious symptom of the borer’s presence is yellowing or dying foliage, which may take months to occur. Another telltale sign is the tiny D-shaped exit hole left by emerging adult beetles on the branches and trunks of ash trees. Vertical splits in the tree bark caused by callused tissue that forms around larval feeding galleries are also evidence of the beetle’s presence, Brewer said.

Infested trees often lose 30 to 50 percent of their canopy in only one year and die between two and 3 years of infestation.

Michigan State University researchers are searching for a method to control the borers, but what they’ve come up with so far is only 90 percent effective. That’s not good enough, experts say, because there’s always the chance enough borers will escape to infest other trees.

Michigan’s Department of Agriculture imposed a quarantine within the 13-county region where the borers were detected and is following a take-no-prisoners approach. Officials scarcely batted an eyelid before deciding to cut down more than 15,000 trees in Kent County after an infestation was detected in a handful of newly planted ash saplings at a local Home Depot store.

Drastic steps? Without a doubt, said Brewer. Yet without such harsh measures, he said, there is the real risk that the beetles could spread beyond the quarantined region to Michigan’s 700 million ash trees and, ultimately, to forests throughout the United States.

Much is at stake, Brewer said, and that is precisely why he believes it is so important to keep an eye peeled for signs of beetle infestation in Alabama.

“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.”

In the case of forest pests, there is more to consider than just environmental and aesthetic issue, Brewer said. Often overlooked is the issue of human safety.

“In an urban setting, a dead tree is not only unsightly but dangerous. Just imagine the trouble that would ensue if someone were injured or even killed by a falling tree.”

Brewer is the first to concede he has his work cut out for him. He hopes to work closely with Extension agents and others throughout the state to closely monitor trees for symptoms as he did with gypsy moths. On the other hand, he’s hamstrung because the technology used to monitor for gypsy moths doesn’t work with borers.

“Unfortunately, with emerald ash borer, there are no traps, no attractants and no pheromone,” 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.”

Problems associated with imported pests such as gypsy moth and emerald ash borer are likely to get worse in the next few years --- factors Brewer attributes to increased travel often associated with more international trade.

“There’s no question that the biggest aid to insect movement is humans, though these pests do pretty well on their own,” he said. “In the old days, when people traveled across oceans in sailing vessels, the insects probably died in transit. The advent of modern travel certainly has changed all that, making it much easier for insects to travel from one continent to another. It’s one of the costs of progress.”

[Source: Dr. Wayne Brewer, Alabama Cooperative Extension System Entomologist and Auburn University Professor of Entomology, (334) 844-2935; Writer: Jim Langcuster, Extension News and Public Affairs Specialist, (334) 844-5686.]

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