This article has been reprinted courtesy of The Ohio Planner's News, the newsletter for the Ohio Planning Conference, Ohio's Chapter of the American Planning Association.

Ohio’s estimated 5 billion ash trees could soon disappear at enormous cost to cities, counties and homeowners. The culprit? A mere half-inch-long insect called the emerald ash borer. A native of Asia, the emerald ash borer attacks all species of native ash trees. Its larvae eat through the tree’s soft tissue, disrupting the flow of nutrients and killing the tree in as little as one year. In Michigan, where it was first spotted, the insect has killed over 15 million trees; Ohio has already lost 280,000 trees. The infestation is resulting in millions of dollars in removal and tree replacement costs.

Containment efforts are slowing the emerald ash borer’s spread in Ohio, but a statewide invasion is generally considered not a question of “if,” but of “when.” Planners can mitigate the economic impact by planning ahead.

Planners should start with an ash reduction plan, recommends Marianne Prue, Ohio Emerald Ash Borer Urban Forester. The plan should include an inventory of ash trees—quantity and location—and a timeline for removing the trees before they are infested. Dead ash trees are exceptionally brittle, creating a significant public safety threat and driving up removal costs. For this reason, the plan should prioritize removal in those areas where dead trees pose the greatest risk.

“The intent is for cities and municipalities to remove and replace ash trees on a schedule that their budgets can support,” said Prue. “Cities can’t afford to take a wait-and-see approach.” She points to Ann Arbor, Michigan, as an example of the danger of not planning. The city faces a $2 million price tag to remove over 10,500 dead ashes.

The plan should also include a replacement tree strategy. Amy Stone, OSU Extension Educator for Lucas County, suggests that planners emphasize tree diversity when selecting replacement trees. “We are a global society, and chances are that other invasive pests and diseases will be imported. Encouraging diversity now can minimize problems from future invasive species,” said Stone. Insecticides are a potential weapon, but one that has not proven 100% effective and thus is not recommended by Ohio State University Extension for use outside of quarantined areas. This option also has associated costs that must be budgeted for, as the trees must be inoculated annually.

Cities can avoid the plight of Ann Arbor if they prepare now.

Thais Reiff is a Master Gardener Volunteer and Emerald Ash Borer Specialist; Bethany Meisinger-Reiff is Greene County Master Gardener, and she can be reached at bethany@ehron.net.
 

For more information on the emearld ash borer in Illinois:

• The Illinois Department of Agriculture has a hotline at 800-641-3934 for extension-confirmed infestations.
• Illinois Emerald Ash Borer Readiness Plan
• USDA Forest Service
• General Information
• USDA Information