Asian Beetle Spreads to Maryland

An invasive Asian beetle that attacks and destroys ash trees has been discovered in a Prince George's County nursery, and 27 trees from the nursery that might have been infested by the emerald ash borer have been planted at three sites in Maryland and one in Virginia.

As of Monday, officials with the Maryland Department of Agriculture had identified three sites in Prince George's – near Suitland, in Laurel and in Fort Washington. The Virginia site is in Vienna in Fairfax County.

Investigators will be visiting the sites in coming days to determine whether the ash trees from the nursery have been infested with the emerald ash borer. They also are planning to conduct surveys of trees within a half-mile radius of the sites to ensure the insect has not spread. Regardless of the findings, the 27 trees will be destroyed, said Sue duPont, a spokeswoman for the Maryland Department of Agriculture.

Maryland is the third state in which the invasive insect has been found, following discoveries of the pest in 13 Michigan counties in 2002 and one Ohio county in 2003. If the trees in Vienna are found to be infested,
Virginia would be the fourth state.

The insect has caused enormous problems in Michigan, where at least 5 million trees have been infested and tree populations have been devastated in some areas.

“We will work aggressively to prevent the emerald ash borer from becoming established in Maryland and causing damage to neighborhood and landscaping trees,” Maryland Secretary of Agriculture Lewis R. Riley said in a statement last week. “Preventing the spread of the emerald ash borer is the most important management strategy.”

Unlike Michigan, where ash trees are common in the woods, the trees are considered rare in Maryland forests in all but the westernmost counties. They are, however, common for landscaping in the state and elsewhere in the country. “As a landscape tree, it's easier to get a handle on this,” duPont said.

Nonetheless, the department fears that failure to eradicate the emerald ash borer “could have serious negative economic and environmental impact” on Maryland, where the greenhouse and nursery industry accounted for $303.8 million of the state's $1.4 billion in agricultural sales in 2002, according to Riley's statement.

The beetle was found during a routine inspection of the Prince George's nursery in late August. The U.S. Department of Agriculture identified the insect at its Systematic Entomology Laboratory in Beltsville on Aug. 29.

The emerald ash borer is part of a group of insects known as metallic wood-boring beetles. Adults are dark metallic green, 1/2 inch long and 1/16 inch wide. The larvae are creamy white and are found under bark.

Source: Washington Post