By Carolyn Y. Johnson
Boston, MA (July 7, 2010)- Asian longhorned beetles, a much-feared invasive pest with the potential to devastate New England’s forests, have been discovered in Boston, across the street from the country’s oldest public arboretum.
Six infested red maples bordering a parking lot at Faulkner Hospital in Jamaica Plain were cut down early yesterday morning. Teams of tree climbers and spotters, sent in by federal officials, have begun laboriously examining every tree vulnerable to the beetle within 1.5 miles.
The sighting of the beetles fanned worries that trees would have to be chopped down in treasured open spaces including the nearby Arnold Arboretum, Franklin Park, and Jamaica Pond. The beetle, which thrives on New England’s signature maples, has no known predators in the United States, and infested trees must be destroyed to prevent the insect’s spread.
The insect has “the ability to be the beetle that ate New England,” said Frank Lowenstein, director of forest health for the Nature Conservancy. “The trees that are its favorite food are the very trees that are characteristic of our region.” But preliminary surveys, begun over the weekend, provide reason for cautious optimism.
“The good news so far is this appears to be very localized,” said Ian Bowles, state energy and environmental affairs secretary. Bowles and federal officials said the infestation appears less widespread than one discovered two years ago in Worcester, which led to the destruction of 25,000 trees at a cost of $50 million in federal and state money.
Workers up in the tree canopy and on the ground have not found signs of the beetle in other trees around the hospital. While the insects can fly up to a mile and a half after they emerge from a tree, they are often “lackadaisical” and will lay eggs nearby or on the same tree they emerged from, according to Clint McFarland, director of the US Department of Agriculture’s Asian longhorned beetle eradication program.
The early positive news did not diminish environmental officials’ sense of urgency. They imposed a ban on transporting firewood or woody material outside of a zone within 1.5 miles of the epicenter and asked Boston and Brookline residents in the target area to search their yards and neighborhoods for signs of the inch-and-a-half-long, shiny, spotted beetles with curving black and white antennae.
The USDA, which is coordinating with state and city officials, had 13 workers combing trees yesterday and plans to hire more to inspect tens of thousands of trees in the coming weeks. Since the beetles were found in Worcester in August 2008, arborists around New England have been vigilant. Just two weeks ago, volunteers inspected trees on Boston Common and found no beetles.
The new beetles were discovered during routine groundskeeping, according to Deb LaScaleia, grounds supervisor at Faulkner Hospital. She saw signs of some kind of insect infestation, sawdust created when beetles bore holes, and sent samples to be tested by a private contractor. The presence of the beetles was confirmed, and around 5 a.m. yesterday the trees were removed. About 10 adult beetles were found, and about 40 beetles in earlier stages of development.
It is not known how the beetles reached Boston. One theory is that they arrived in wood products such as firewood. McFarland said scientists will use genetics to try to determine the origins of these beetles. The beetle, which is native to Asia, is an invasive species of much concern in the United States. First detected in 1996 in Brooklyn, N.Y., it also has caused infestations in Chicago and New Jersey, where thousands of trees were removed. While it is not known how the beetles first got to this country, one potential source is wooden shipping pallets.
Besides its lack of predators, the beetle is especially pernicious because it threatens so many types of trees, including maple, elm, willow, birch, horse chestnut, poplar, and mimosa. In the spring, a pesticide can be used to treat at-risk trees to try to prevent future infestation, but once a tree is infested, the only option is to cut it down and turn it into chips or burn it.
The beetles chew an oval-shaped pit in the bark of a tree in the summer, and females lay one egg in each pit. When those eggs hatch, larvae tunnel into the heart of the tree, where they eat the wood and spend the winter. When the larvae are grown, they emerge as adult beetles the following summer by boring their way to the surface of the tree. While a single year of infestation will not kill a tree, the holes and tunnels the beetles make structurally weaken a tree and make it vulnerable to disease.
“This is a huge deal,” said Bob Childs, an entomologist at the University of Massachusetts Amherst. He said the new find is of particular concern because “the Arnold Arboretum is just a gem among gems. It’s a spectacular planting [ground] with great historic value, not to mention botanical value.”
Julie Crockford, president of the Emerald Necklace Conservancy, a public-private partnership devoted to parks protection and public education, said that teens working in Boston parks this summer will be trained to monitor for the beetle. “We’ve been waiting for this shoe to drop, and now it has,” Crockford said. “I hope we can contain it.”