Invasive Asian longhorned beetle has potential for wide reach in region’s forests
By Summit Voice
SUMMIT COUNTY — An Asian beetle that arrived in the U.S. via wooden packing material in the 1990s could spread into forests near northeastern cities, according to a study appearing in the latest issue of the Canadian Journal of Forest Research. Previous eradication efforts in Boston, New York and other U.S. cities have focused exclusively on urban street trees.
The invasive Asian longhorned beetle is extremely destructive, and the burrowing larvae cause damage to the vascular structure of a tree in a similar manner to the mountain pine beetle.
The beetle was detected in Worcester, Massachusetts in 2008 by a private citizen. Forests surrounding Worcester are part of a heavily wooded corridor stretching from New York into New Hampshire, Vermont, and Maine. This is the only outbreak so far that has allowed the beetle to invade nearby closed-canopy forests.
“From our work it became apparent that ALB was readily moving through forests and attacking trees, making it a threat to forests in the region, ” said Kevin Dodds, an entomologist with the U.S. Forest Service.
David Orwig, a forest ecologist at the National Science Foundation‘s Harvard Forest Long-Term Ecological Research site, said that “the ALB apparently has been in the Worcester area for at least 10 years, and undetected, could have easily spread to even larger tracts of continuous forest.”
In forests, the beetle disproportionately attacks large maple trees. At one of the forested study sites in a suburb north of Worcester, nearly two-thirds of all the maples were infested, including red, sugar, and Norway maples. Red maples, the study shows, are particularly vulnerable to infestation. Red maples are widespread in New England and central to the region’s fall foliage tourism industry, which attracts more than one million visitors annually to New England and generates $1 billion in revenue.
According to Orwig, “If the ALB continues to spread outside Worcester, the abundance of red maples could provide a pathway for its dispersal throughout New England and other parts of eastern North America.”
The ALB eradication efforts in these stands have involved tree harvest and consequently have led to shifts in forest composition from maple to oak, which may have cascading effects on soil processes and ecosystem function.