After Five-Year Absence, Destructive Beetle Discovered in Trees in Herndon, Newington

The emerald ash borer, a tiny exotic beetle responsible for killing at least 40 million ash trees from Michigan to Maryland, has reappeared in Fairfax County after a five-year hiatus, officials said yesterday.

The insect -- no more than one-half-inch long and one-eighth-inch wide -- was found this week in 30 ash trees in Herndon and at least 10 in Newington. Fairfax and Prince George's counties are believed to be the only Washington area jurisdictions that have been invaded by the beetle, which has burrowed its way through at least seven states since it appeared in southeastern Michigan in 2002.

The insects infested about 120 trees in Vienna in 2003, and Virginia officials ordered more than 230 trees destroyed at or near Colvin Elementary School, where the insects were found. County officials said last night that it is unclear how the borers made their way back to Fairfax.

"This is bad news to hear that this insect has returned," said Elaine Lidholm, director of communications for the Virginia Department of Agriculture and Consumer Services. "This has very serious implications for ash trees. . . . The state and county will work aggressively to remove the insects and ensure they do not come back."

She said state officials probably will destroy not only the infected ash trees but also those nearby. There are about 2 million ash trees in Fairfax, county officials said.

The borer is native to eastern Russia, northern China, Japan and Korea, according to Michigan agriculture officials. Experts said they think the beetles reached the area outside Detroit in ash wood used for securing cargo in ships or for packing heavy goods.

"This thing has had its way with us," said Ken Rauscher, director of the Pesticide and Plant Pest Management Division in the Michigan Department of Agriculture, where officials estimate that 30 million ash trees have died in six years.

Most of that devastation is in southeastern Michigan, but tens of millions more trees have been lost in Ohio and Indiana. Rauscher said that although officials have tried to quarantine wood in certain sections of Michigan, their best hope for eradicating the beetle is introducing a tiny wasp that they hope will prey on the insects.

The beetle, which has a cylindrical shape and metallic green sheen, was discovered in southern Prince George's in 2003, where 121 trees were infected and later destroyed, along with about 1,000 more as a precaution.

Symptoms of an infected tree include thinning of the canopy and major branches because the bugs cut off the tree's ability to distribute water. Sometimes ash trees push out sprouts from the trunk after the upper portions of the tree dies.