State forestry officials announced a quarantine Wednesday for all of York County to try to slow the spread of a destructive species of beetle by limiting the transport of infested wood.

The discovery of emerald ash borer beetles in western York County in September was only the second time the invasive species has been found in Maine. Adult beetles were recovered from traps in Acton and Lebanon, according to state officials. Live larvae of the destructive forest pest was found for the first time in Acton and Berwick last month.

The Maine Department of Agriculture, Conservation and Forestry announced a formal quarantine for the emerald ash borer for all of York County and the northeastern corner of Aroostook County. An emergency order has been in place to limit the movement of infested ash from areas where it has already been discovered.

The emerald ash borer poses a threat to the state’s ash trees, an important economic species in Maine. Photo courtesy Dr. James E. Zablotny, USDA

Last year, Maine entomologists found the state’s first emerald ash borers in several locations around Madawaska along the Maine-Canada border. Those insects were believed to have crossed over into Maine from infestations in neighboring New Brunswick. But officials say the transportation of emerald ash borers – as well as other destructive, invasive pests – in nursery stock or firewood poses a threat in Maine.

A native of Asia, emerald ash borers have killed millions of trees in the U.S. and Canada since being discovered in 2002 and are regarded as one of the most destructive forest pests in North America. It has been found in at least 35 states and four Canadian provinces.

The small, metallic-looking beetles lay eggs on ash trees and the hatching larvae then tunnel under the trees’ bark, causing extensive damage that typically results in tree death within three to five years. Although there are methods to control the spread of the emerald ash borer, experts have yet to devise a way to eliminate the pests once they are established.

The quarantine rules prohibit movement of ash nursery stock from the quarantine area and regulate the movement of hardwood firewood, untreated ash lumber and hardwood chips and other ash products with bark.

“A quarantine can help slow the spread of this destructive insect into uninfested areas,” state entomologist Allison Kanoti said in a statement. “That gives businesses, Native American craftspeople and artists that use ash as well as homeowners, landowners and municipalities who care for ash across the state additional time to consider their options and make plans for a future with EAB.”

Maine forests have more than 400 million white, green and brown ash trees that are at risk of infestation, according to forestry officials. Although accounting for just 4 percent of Maine’s hardwood forest resources, ash trees fill an important cultural and economic niche in Maine.

Ash is used to make baseball bats, snowshoes, furniture, canoe paddles and other products in Maine, and the state’s ash forests have an estimated overall commercial value of $320 million. Maine’s Indian tribes have for generations used ash to weave baskets, for the thwarts and gunwales of birch-bark canoes and in other tribal crafts.

Staff members from the Maine Department of Agriculture, Conservation and Forestry are teaming up with with federal forestry officials to work with the public and impacted industries to ensure compliance with the quarantine.

Gillian Graham can be contacted at 791-6315 or at:

ggraham@pressherald.com

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