Purple traps reveal no new infestations

The unusual purple contraptions posted in trees earlier this year — part of a survey looking for a deadly beetle threatening forests — documented the critter hasn’t invaded locally yet.

The creature apparently has not migrated to any new counties in Virginia, authorities say.

But if it does, as officials say is possible, the bug could devastate ash trees in Virginia’s rich forest lands, and the beetle has become more prevalent in areas where it does exist, said a Michigan-based expert.

A total of 5,500 traps were installed in Virginia as part of a survey to determine the extent to which the emerald ash borer has infiltrated the commonwealth. The entire survey was comprised of 61,500 traps installed in the lower 48 states.

Nationwide, the survey revealed 59 new detections of the beetle, but no new infestations were detected Virginia or in states that have yet to be affected, said Sharon Lucik, of the U.S. Department of Agriculture. Some states have not yet completed their reports, she said.

So far, the state has quarantined the counties of Arlington, Clarke, Fairfax, Frederick, Loudoun, Prince William, Fauquier and the cities of Alexandria, Fairfax City, Falls Church, Manassas, Manassas Park and Winchester.

Nationally, all off of West Virginia and Indiana and the lower peninsula of Michigan are quarantined, said Sharon Lucik of the U.S. Department of Agriculture. Quarantine means ash trees, logs or nursery trees cannot be transported out of the area.

“We know that they’re good fliers,” Lucik said, and they could expand their range, she said.

Besides, Virginia, since 2002, infestations have been detected in 13 other states: Illinois, Indiana, Iowa, Kentucky, Maryland, Michigan, Minnesota, Missouri, New York, Ohio, Pennsylvania, West Virginia and Wisconsin, according to the U.S.D.A.

The beetle is metallic green and half an inch long. Adult beetles are not the menace; the danger to ash trees comes from their larvae, which tunnel beneath the bark, disrupt the tree’s ability to take food and water and eventually starve and kill it, according to www.stopthebeetle.info.

The ash borer likely arrived in the United States inside wood packing material from Asia. Since its discovery in southeastern Michigan, the bug has killed tens of millions of ash trees in Illinois, Indiana, Iowa, Kentucky, Maryland, Michigan, Minnesota, Missouri, New York, Ohio, Pennsylvania, Virginia, West Virginia and Wisconsin, according to the website.

Another survey is planned for next year, Lucik said.

Purple traps are used because this type of beetle is attracted to that color, and to red.

In their adult stage, the beetle flies around ash trees, eating bark and leaves and searching for a mate.

The beetles typically do not travel more than a half-mile, and human behavior causes most of the spread of the infestation, by such activities as inadvertently moving infested firewood and other products, Lucik said.

“This non-native pest poses an enormous threat to our urban and rural forests,” according to the U.S.D.A.’s inspection service website, www.aphis.usda.gov. The beetle kills stressed and healthy trees, “and is so aggressive that ash trees may die within two or three years after they become infested.”

“If it is not contained and managed, the impact of emerald ash borer beetle in North America will be similar to that of the devastation caused by two fungal diseases, chestnut blight and Dutch elm disease, which destroyed dominant species of woodland and urban forests in the 20th century.”

All 16 native species of ash trees are hosts for the beetle.

The agricultural impact in Virginia and other states could be substantial, and effects could include decreased property values, loss of the ash wood supply, decreased air quality, and increased electricity use during hot weather and loss of tree cover in campgrounds, according to the inspection service.

To report a fallen or damaged trap, call (877) 207-9406 or (865) 482-5000. The survey is a collaboration by the U.S.D.A., the inspection service and state and tribal officials.

The U.S.D.A. also has a staffed hotline, (866) 322-4512. Homeowners often call the number from a cell phone as they are examining the trap, to ask what it is, Lucik said.

Reach Scott Marshall at (434) 946-7196 or smarshall@neweraprogress.com.