Last call for ash trees

10/2/2012

Time is running out for a state program that covers as much as 40 percent of the costs private-property owners incur to have dead or dying ash trees taken down. After Nov. 30, they’ll be on their own.

Emerald ash borers crossed into Ohio in 2003, a year after they were found to have infested a Detroit suburb. The beetles likely established themselves in Michigan years earlier, after coming from China in shipping crates.

Homeowners have faced the choice of spending large sums, sometimes thousands of dollars, to take down their dead ash trees or assuming liability for them. Many insurers rewrote homeowner policies to exclude coverage for injuries and accidents caused by ash trees and their branches. The trees become brittle soon after they die.

This last call on a program administered by the Ohio Department of Natural Resources is one of the final local battles of a hard-fought war against one of North America’s worst invasive species. U.S. and Canadian scientists made a valiant effort to cut off the destructive pest from its only known food source.

But they came to realize — after millions of dollars were spent to clear-cut swaths of healthy as well as diseased ash trees — that they never managed to surround the ash borer. The U.S. Department of Agriculture has poured money into developing insecticides, as well as hybrid trees that might withstand onslaughts by the insect. But the future looks bleak for most of the 10 billion ash trees east of the Rocky Mountains.

The destruction wrought by emerald ash borers, which are not native to North America, offers a graphic illustration of why public officials must take invasive species more seriously. Another invasive threat, Asian carp, jeopardizes the Great Lakes region’s $7 billion fishery.

There’s also a hard lesson of diversification: Ash trees were seen as an ideal replacement for American elms crippled by disease decades ago. Developers and property owners made the mistake of becoming too reliant on the species.

The Ohio DNR program covers 40 percent of the cost of removal of two ash trees per property owner. It requires estimates from three certified arborists. Owners in Lucas, Wood, Erie, Sandusky, Ottawa, Huron, and Lorain counties are eligible. 

 The saga over ash trees is winding down locally, but not globally. Lessons about invasive species and biodiversity remain to be learned.