Fighting back against emerald ash borer

3/8/2006

The emerald ash borer may have brought down millions of trees, but some scientists are trying to bring them back in Toledo. Pat O Brien, forestry inspector for the city of Toledo, says he lives in Point Place, where hey have taken down many ash trees. "The streets are almost bare. So I really know how people feel."

In partnership with Ohio State University, the city of Toledo has planted about 200 ash trees to see if they can come up with a species that will be able to fight off the emerald ash borer.

They have planted 20 different kinds of ash.

American, White, Blue, and Green ash are on the list as well as European, Oregon, Chinese, and Manchurian. Scientists say they may have the best luck for resistance with Chinese and Manchurian Ash because they are native to Asia and so is the ash borer.

This is the second test plot in the quarantined area. They have also planted 600 ash trees in Novi, Mich. Scientists are monitoring them closely. "We are taking this proactive step," says Mr. O Brien. "If we can find any resistance, it will have to come from the same place as the insect."

The trees were planted two years ago along Wallace Boulevard near the railroad tracks. Davis Sydnor, professor of urban forestry for Ohio State University, says they are trying to figure out which trees will develop their own survival mechanism to fight off the emerald ash borer. He thinks it will be another year before they see any evidence of an ash borer on these young trees.

The borer usually likes to feed on trees with a trunk diameter over two inches. "The insect feeds at the top of the tree canopy, so a homeowner doesn t even know they are there," says Sydnor.

By the time you start to see the D-shaped holes on the trunk and branches of the tree, it is too late. He says new research shows that trees don t actually die in one season. It takes five to eight years for a tree to die.

But he says it seems quick because the bugs can t be detected until they are three to five years into their life cycle.

"Ash is heavily planted in urban America," says Mr. O Brien. "About 5 to 8 percent of our total tree population is ash."

The city is still aggressively taking down infested ash trees.

Mr. O Brien says there are about 6,000 ash trees in the city and theoretically they could all die at the same time. "And they could also end up to be a hazard all at the same time," he says. The city says they will also remove the stumps and replant a replacement tree by fall.