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DNR issues quarantines to fight ash borer

By Curt Slyder
Wednesday, January 25, 2006

WEST LAFAYETTE, Ind. - Local tree experts are getting a bit nervous about an insect that could wipe out Indiana's ash tree population.

The Indiana Department of Natural Resources issued quarantines for Hamilton and Marion counties Monday after local officials there discovered evidence the emerald ash borer has infested ash trees in Carmel and in Fishers. Carmel is only 50 miles from Lafayette.

People in quarantined counties are prohibited from taking ash trees or wood from ash trees out of the counties without special permission, said state entomologist Robert Waltz.

Many insects attack trees, but the emerald ash borer is different, warned Jodie Ellis, Purdue University's exotic insects education coordinator and an expert on the emerald ash borer.

"If the emerald ash borer became established in our area, over a period of several years we would see every single ash tree attacked and die," Ellis said. The ash borer "kills 100 percent of the trees it attacks."

Ash, a popular hardwood long used in urban landscapes, has been a part of American sports since the 1890s when Louisville Slugger started manufacturing a baseball bat with ash. The company, which is the official bat maker for the professional leagues, still makes its pro baseball bat from ash.

D. Cappaert, Michigan State University

Worst case scenario

In December, Decatur Indiana spent $1 million to destroy all of its ash trees in the hope of stopping the spread of the Asian beetle that is 100-percent fatal to North American ash trees.

If such a worst case scenario becomes necessary in the Lafayette area, it would definitely be noticed. Of the more than 4,100 trees that line West Lafayette's streets, 902 of them are ash trees, said Bev Shaw, West Lafayette's greenspace administrator. "Consider one out of every four or five trees as you go down the road being gone," she said. "It's a huge impact."

Fifty miles is not far for such an aggressive insect to travel, hitching rides primarily on firewood often cut and transported by people who don't recognize the tree as an ash.

"That's pretty close," said Tippecanoe County Parks director Allen Nail. Though he's unsure if the ash borer will make its way into Tippecanoe County, "It's a big concern," Nail said.

The Journal and Courier was unable to obtain data on numbers of ash trees in Lafayette. But numerous trees in area parks and on private property are ash trees.

According to Waltz, there are nearly 300 million ash trees in Indiana.

How they kill

The green-colored beetles are about half an inch long as adults, Ellis said. They like to eat the leaves of ash trees. They live up to 20 days and can fly up to half a mile from where they are born.

But the big problem is their larvae, Ellis said. Adults lay eggs on the trees. When the larvae hatch, they burrow into the tree and feed on its vascular system, she said.

"One insect will kill a tree," said Rick Meilan, an associate professor of molecular tree physiology at Purdue. He is researching a genetically enhanced ash tree that would resist the ash borer.

Meilan estimates his team is about two years away from being able to plant such trees.

Though pesticides will kill the ash borer, they must be applied carefully. "The trick is getting the right amount to the right place," Waltz said.

Waltz and Ellis advise anyone wanting to treat their trees with pesticides or chemicals in order to prevent the ash borer to seek help from a certified arborist.

"If you do it wrong, it won't work," Ellis said.

Shift in policy

The recent Carmel and Fishers infestations created a shift in the state's policy to handle the insects. Until then, the state was using federal funds to cut down all the ash trees within one-half mile from the site of an infestation, Ellis said. But that was becoming cost prohibitive.

The new policy calls for citizens to be aware of the dangers and to obey any quarantines in effect. Citizens also will be financially responsible for their own trees, Ellis said.

People should look for telltale signs in ash trees, Ellis said. If an ash tree is dying from the top down; is riddled with small, eraser-sized, capital-D-shaped holes; or has S-shaped feeding tunnels under its bark; it could be infested with emerald ash borers, Ellis said.

Ellis and Waltz stongly urged people not to transport firewood. "That's the number one way they are spread," Ellis said. Firewood should be kept inside the county where it's cut. If possible, burn the firewood the same year it's cut, Ellis said.

Find out more
For information about the emerald ash borer and ash trees, go online to