City on Cusp of Eradicating Asian Longhorned Beetle

Email a Friend

August is the month the scourge of New York, the Asian longhorned beetle, emerges from the tree it’s been devouring from the inside out.

But after felling 6,275 infected trees in New York City, the USDA said Manhattan is in the home stretch, one year away from a declaration of total eradication, while New Jersey and Staten Island are set to achieve it in 2014. However, for Brooklyn, Queens, and parts of Long Island, it may take several more years.

The beetle is a shiny jet black with splotchy white spots on its one-inch long body, has six bluish tinted legs and an antenna longer than the length of its body. In its lifetime the female will lay up to 90 eggs under the bark of the tree that it attacks. Two weeks later the larvae will tunnel into tree. When it emerges, often in late summer, it leaves dime-sized hole in trees (pictured below).

Patient zero most likely arrived in Brooklyn in wood packing materials for water pipes shipped from China in the late '80s or early '90s. It went undetected for several years — until dime size holes began appearing in Brooklyn trees in 1996. By then it was too late. The Asian longhorned beetle had already established a robust population. With an appetite for 13 native trees and no predator to hinder its growth, it spread to all boroughs.

“If you took a cross section of an Asian longhorned beetle infested tree, it would look like a piece of Swiss cheese,” said Rhonda Santos, a spokesperson for the USDA. “It’s really a sad tale for trees because the tree will eventually die — it’s essentially being eaten from the inside out.”

The only way to eradicate the beetle is to remove the infected tree and monitor the area. To declare “eradication” the USDA must have no beetle spotting in “four survey cycles,” although survey cycles vary depending on the area of infection and whether there are ground surveyors or tree climbers. On occasion, insecticide may be used on individual trees.

Troy Weldy, director of Ecological Management at the Nature Conservancy, said the beetle can damage the economy and the ecology of the area. If it spreads north of the city, which it hasn’t yet, it could damage New York’s forestry and maple syrup industry, and is a public safety concern. “It does drill deep into the tree and you can have a large number within the tree — it can structurally weaken the tree and cause hazards for individuals that would be walking near the trees,” he said.

The last beetle spotting in New York City was in November 2005, but the Asian longhorned beetle has been spotted as far as Ohio and Chicago, and was found in Worcester, Mass., in 2010, where it has yet to be eradicated. The 13 types of trees it likes to infest include birch, elm, ash and maple trees. However, it does not infect linden, apple, crabapple and red bud trees.

If you spot the beetle, experts say don’t smash it, take a picture and upload to the USDA’s website. Also, contact the USDA if you see the dime sized hole in a tree.

Dime size holes left in trees by the Asian longhorned beetle.

( Courtesy of the USDA )

Asian beetle larvae.

( Courtesy of the USDA )

Asian longhorned beetle.

( Courtesy of the USDA )

Workers removing Asian longhorned beetle limbs.

( Courtesy of the USDA )