New Jersey Department of Agriculture officials confirmed that the emerald ash borer, an invasive beetle that attacks and kills ash trees, has been found in Somerset County.
A landscaper investigating unhealthy trees in a retail area in Bridgewater last week alerted the department.
Inspectors took samples and insect larvae were sent to the U. S. Department of Agriculture’s Systematic Entomology Laboratory where the specimens were confirmed.
For the past four years the Departments of Agriculture and Environmental Protection have participated in an emerald ash borer survey, but none of the beetles were found in the more than 300 traps set up around the state.
Emerald ash borers had already been detected in Pennsylvania and New York counties bordering New Jersey.
“We have been rigorously monitoring the emerald ash borer’s movements and educating the public about what to look for in case the beetle entered our state,” said New Jersey Secretary of Agriculture Douglas H. Fisher in a news release Wednesday.
“Now, we will be informing homeowners about the actions they can take to protect their ash trees from this tree-killing insect.”
Emerald ash borers, which are native to Asia, are now present in 23 U.S. states and two Canadian provinces. The insect was first discovered in Michigan in 2002 and has since killed tens of millions of trees.
“Since the emerald ash borer has been active just over our borders for quite a number of years, we expected that it would be found in New Jersey eventually,” said State Forester Lynn E. Fleming.
“The DEP will work with the Department of Agriculture and other appropriate agencies to educate landowners on how to identify this invasive beetle and mitigate infestations."
The adult emerald ash borer is a metallic green insect about one-half inch long and one-eighth inch wide, making it hard to detect in the wild.
The female beetles lay eggs on the bark of ash trees. The eggs hatch and the larvae bore into the bark to the fluid-conducting vessels underneath. The larvae feed and develop, cutting off the flow of nutrients and, eventually killing the tree.
The insect attacks and kills North American species of true ash, with tree death occurring three to five years following initial infestation.
The state will survey trees in the area surrounding the initial find to determine the extent of the infestation. It is expected that a federal quarantine will be expanded to include New Jersey.
Homeowners who own ash trees can take steps to protect their trees. Treatment products are available at local retail establishments and state-certified pesticide applicators can treat for the insects.
Signs of infestations include: canopy die back beginning at the top of the tree and progressing through the year until the tree is bare; sprouts growing from the roots and trunk; split bark with an S-shape gallery; D-shaped exit holes; and more woodpecker activity, creating large holes as they extract the larvae.
To prevent spread of the beetle, do not move firewood, advise state officials. Firewood is a vehicle for movement of tree-killing forest pests. Use locally-sourced firewood when burning it at home and when travelling, burn firewood where you buy it. Make sure to burn all wood purchased.
Residents are encouraged to report signs of the beetles to the Department of Agriculture at 609-406-6939.
More information about emerald ash borer is available on the state's website.