Traps Deployed in Borer Battle

Purple traps are being deployed in Maryland to eradicate Emerald Ash Borers. Of the 61,000 traps nationwide, Maryland has used 2,600.

Emerald ash borers have already killed tens of millions of ash trees across the United States since showing up in wood packing material in Michigan in 2002 and in nursery trees shipped to Maryland a year later.

Federal and state government have rallied to save the popular tree, which is used in landscaping, for tool handles, flooring and baseball bats. More than 61,000 of the purple prism-shaped traps have been deployed across the country - about 2,600 of them in Maryland - to spot the little half-inch long beetles. This is the time when traps are deployed because the borers tend to emerge from where they hatched and fly to other trees to spread their devastation.

The purple color attracts borers, and the traps' appeal is magnified by bait suspended inside them that gives off ''essence of ash tree.'' But U.S. Department of Agriculture spokeswoman Sharon Lucik says the attractions are only strong enough to draw borers from trees nearby, not from far away.

The traps by themselves can't catch enough beetles to stop them. So USDA experts have imported three different species of non-stinging wasps from China, where they are natural predators of the ash borers. The wasps, which experts say pose no risks to other species, have been released in Maryland and seven other states among beetle-infested trees, where they kill borer eggs and larvae. First released last year, the wasps seem to have survived the winter, Lucik said.