News & Events In Common Newsletter Winter 2008-2009 Portrait of a Tree Killer
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Volume 6 • Number 4 • Winter 2008-2009
Portrait of a Tree Killer
Anoplophora glabripennis is flashy and slow… Even by regular Anoplophora glabripennis standards, which tend to be imposing in any light, the Asian longhorned beetles of Worcester are impressive. While ALB is typically described as being 1.0-1.5 inches long, many are somewhat smaller, notes Bob Childs of UMass Extension. The Worcester county ALB population, however, seems to hug – and sometimes push – the upper limit. Researchers say they are seeing insects larger than those found in China, the pest’s home turf. “This is the Darth Vader of insects,” insists Deborah Swanson of UMass Extension in Plymouth County. Swanson has long worked closely with Childs and with forest insect ecologist Joe Elkinton of the UMass Amherst Department of Plant, Soil and Insect Sciences. They form a team that was the first to identify the European winter moth in Massachusetts. It is a pest that damages and defoliates trees. By contrast, ALB larvae burrow deep into a tree, destroying critical tissues and – without exception – killing it. Since first appearing in Brooklyn in 1996, and then being spread to Long Island via the transportation of infested wood, ALB has changed the treescape of several urban areas of New York, New Jersey and Chicago, causing an estimated $270 million in damage. The cost of its destructive potential is estimated at $41 billion. The good news, if it can be called that, is that ALB is fairly well understood and researchers know how to stop it. Pat Bigelow of Bigelow Nurseries in Boylston points out that what makes ALB so impressive also makes it easy to spot. “This is not an aggressive bug. In fact, it’s a lazy sucker. It finds itself a place it likes, and it doesn’t seem to move a lot until it has to,” she said. Childs adds that ALB doesn’t fly well, and that makes it difficult for adults to travel more than 1.5 miles, and that’s with a good stiff wind. 
Photo: USDA By strictly regulating a 1.5 mile radius around each infested tree, officials can stop its spread, unless the transportation and improper disposal of wood products give the critter a free ride. In the past, all of the vulnerable trees within the regulated area might have been cut down. In Worcester, the strategy will be to cut down infested trees and inoculate healthy trees internally with a pesticide. “It’s a risk,” said Childs. This is how ALB does its dirty work: An adult female, active only in the summer and early fall, will lay up to 90 eggs in the bark of a tree – Norway maples are a favorite. In 10-15 days, the larvae hatch and start to bore into the tree, moving deeper as they winter over and feed on tree tissue. Starting in July, new adults emerge from the tree, leaving internal destruction, and only neat holes about the size of a dime on the outside. This is how to be on the lookout for ALB: the sheer size of the ALB’s black with white spotted body, with prominent antennae that have alternating segments of white and black, is a giveaway – as are the perfect dime-sized holes they leave behind. Even then, though, it’s not always easy. ALB tends to look like several other beetles, including the whitespotted sawyer, northeastern sawyer and banded alder borer. In addition, only about a third of infested trees are identified from the ground. Tree climbing “smoke jumpers” can double that rate. And in order to stop the spread, identification must occur early on. This is how to stop ALB: the best way to stop ALB, say federal APHIS officials, is before they reach the U.S. As of 2005, all wood packing material, such as pallets and crates, entering the country must be heat treated or fumigated. While research continues, however, the pesticide imidacloprid injected into a tree trunk remains the only direct way to help stop the spread of ALB once it shows up. By the time the pesticide becomes necessary, however, it is already too late, and containment is the only option. Public education, along with special training and certification of those who handle wood products, has become critical. In order to contain the beetle, it is necessary to stop transportation of firewood or wood products out of a regulated area. Infested wood can be burned, but only within the regulated area, and it must be burned this winter. After all, big, lazy ALB enjoys a free ride. Credits:
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