Second infestation of emerald ash borer found in N.H.
This video from the Minnesota Department of Agriculture details the lifecycle of the emerald ash borer. Merrimack County hardwood has been under quarantine since the bug was detected in Concord in April 2013.
In this photo taken Thursday, Nov. 7, 2013 the tiny larva of an emerald ash borer is seen in a tree in Concord, N.H. The destructive beetle, a native of China, targets ash trees and was spotted along a six-mile stretch of the Merrimack River last March. Scientist hope to control the outbreak and minimize the damage to the state's ash tree population. (AP Photo/Jim Cole)
FILE - This undated file photo provided by the Minnesota Department of Natural Resources shows an adult emerald ash borer. The insect that could threaten one of South Dakota's most populous tree species moved even closer to the state in the past year. The emerald ash borer last year was found in Union County in southwestern Iowa, as well as in Boulder, Colo. South Dakota State University forestry expert John Ball said he thinks the Asian beetle will be found in South Dakota within five years. (AP Photo/Minnesota Department of Natural Resources, File)
State forestry officials have confirmed a second infestation of emerald ash borer in Merrimack County, an area about 3 miles long by 2 miles wide on the border between Canterbury and Loudon.
They said the infestation appears to be unrelated to the first New Hampshire spotting of the invasive pest in Concord last spring.
There is no known eradication method for the beetles, which are native to Asia and are responsible for killing millions of ash trees in 22 states since they were first discovered in Michigan 12 years ago. They have spread quickly from state to state, largely because of people moving firewood between regions, experts said.
“We will be dealing with the emerald ash borer for the rest of our careers,” said Kyle Lombard, forest health specialist with the Division of Forests and Lands. “There’s no getting rid of it where it is, but we’re working to slow the spread.”
New Hampshire’s roughly 25 million ash trees make up between 4 and 6 percent of the state’s forested area and about 1 percent of the timber industry.
So far, emerald ash borer damage has not been reported outside of Merrimack County, but officials said landowners across the state should check their trees now for excessive woodpecker activity, the most visible sign of infestation.
The birds strip the outer layer of bark off ash trees in their attempts to get at the bugs’ eggs and larvae, exposing the trees’ cream-colored underbark. That damage is most visible now, before the trunks are obscured by leaves.
The beetle’s larvae can kill untreated trees within five years of infection by eating S-shaped channels into the underbark, cutting off the flow of nutrients and water.
A permanent quarantine is in place on ash nursery stock, lumber and wood chips, and all hardwood firewood – not just ash – within Merrimack County. Transporting any regulated items outside the county requires a permit; wood other than ash that is at least 4 feet long does not require one.
Lombard was optimistic that most people have stopped transporting firewood into the state. A 2012 survey showed about 10 percent of people admitted bringing in out-of-state wood. That’s down from about 40 percent in 2006, he said.
Gov. Maggie Hassan plans to announce a statewide emerald ash borer awareness week in late May to encourage landowners to inspect their trees and plan for possible infestations.
“Regardless of what community you live in, you need to determine if you have an ash resource, and think about your long-term goals for that resource, your budget for treatment, removal or replacement so that if emerald ash borer is found in your area, you have a plan,” state entomologist Piera Siegert said. “You want to be the one deciding how to manage your trees, rather than having the beetle make the decisions.”
Towns, cities and landowners with infested ash trees have few options. They could remove an infected tree or inject it with pesticides, but both are expensive.
State foresters can release wasps that prey on the beetle, but they said last year the infestation was not large enough to warrant that move.
(Sarah Palermo can be reached at 369-3322 or firstname.lastname@example.org or on Twitter @SPalermoNews.)