Emerald ash borer

The half-inch long emerald ash borer is deadly to trees. (Baltimore Sun / June 15, 2011)

Just weeks after it turned up in Howard County, the emerald ash borer has been detected in Anne Arundel and Allegany counties.

Maryland agriculture officials have responded by placing all Maryland counties west of the Susquehanna River and the Chesapeake Bay under quarantine. Movement of ash wood and trees, and all hardwood firewood, out of the zone is banned, and all movement of hardwood firewood within the zone is discouraged. "Buy it where you burn it," officials urged.

The quarantine is "the best way to secure Maryland's Eastern Shore, where EAB has not been found to date, and protect our riparian forest buffer plantings," said state Agriculture Secretary Buddy Hance. While federal, state and local authorities continue to search for better controls on the pest, he added, "we rely upon cooperation from the community to follow the quarantine restrictions, not move firewood and to report signs of possible infestation."

The emerald ash borer is an Asian invader first detected in Maryland in 2003, in Prince George's County. It reached Charles County five years later, and was found in Howard County last month. Fatal to ash trees, the insect typically kills its host within three years.

Baltimore City has the state's largest population of ash trees, with an estimated 293,000. There are an estimated 6 million in the city and surrounding counties. Removal of dead trees can cost between $1,000 and $2,000 each. Federal authorities have estimated financial losses in the Baltimore area alone could reach $227 million if the insect becomes established there.

Julie Oberg, spokeswoman for the Department of Agriculture, said the pest's spread to Baltimore and the rest of Maryland west of the bay now appears likely.

frank.roylance@baltsun.com

http://twitter.com/froylance

Maryland weather blog: Frank Roylance on meteorology

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