The Emerald Ash Borer is making a mess of Michigan’s ash trees, but help is on the way.

As the Emerald Ash Borer (EAB) continues its march through much of lower Michigan, with a brief appearance in an isolated area of the eastern U.P., rural electric co-op members are probably wondering how the outbreak will affect them and what they can do to save their trees.

For those folks who are trying to save these stalwarts of the tree world, help may be on the way, according to John Smitley, professor of entomology and project leader for the Emerald Ash Borer at Michigan State University.

“If you decide to treat your trees, you have a very good chance of keeping your trees healthy,” says Smitley, about the latest treatments available to homeowners.

Unfortunately, if your tree is already infested with this tiny critter, your next course of action will be to remove the tree. The most obvious symptom in an infested tree is a die-back in the crown, or upper portion of the tree. Another is the detection of small “D” shaped holes in the tree’s bark.

The decision to treat your tree is a personal one, said Smitley. He said that smaller trees might not be worth the effort. If you decide to treat your trees, there are some products available that just might do the trick.

The treatment of choice for the do-it-yourselfer is a liquid drench systemic that includes the active ingredient imidicloprid. Systemics travel up through the root system of a plant and renders it poisonous to targeted insects. Bayer Advanced Garden Tree and Shrub Insect Control is used to drench around the roots of ash trees. This must be applied the first week of June and repeated each year to be effective, said Smitley. Be sure to read the label instructions, especially about the application and safe handling of this product.

For trees in infestation “hot spots” or quarantine areas, trunk injections with “Ace Caps” in combination with the Bayer drench are recommended, said Smitley. Trunk injections involve tapping into the tree trunk. Homeowners can do this themselves by following directions in a recently released MSU Extension bulletin, “Homeowner’s Guide to Emerald Ash Borer Treatments” (E2955). The alternative is to hire a professional.

Should you decide to hire a landscaping firm or arborist to do the drench
and/or trunk injections, beware that many companies are vying for your business. To ensure you’re hiring an experienced tree care company, check references to see if they belong to any professional organizations, such as the International Society of Arboriculture (ISA) or employ ISA-certified arborists. Get a written estimate or contract, and make sure the company has the appropriate workmen’s compensation and liability insurance.

There are 21 counties quarantined in southeast lower Michigan and 31 outlying infestations. To find the exact quarantine boundaries, log-on to www.michigan.gov/eab. People living in these areas should be aware of restrictions involving the handling and removing of ash materials, including firewood or face fines and possible imprisonment, says Jennifer Quimby, media relations coordinator of the EAB Response Project, Michigan Department of Agriculture (MDA).

“It’s important that property owners adhere to the state’s internal quarantine regulations to help curtail the spread of the pest,” says Quimby. “Property owners can receive the most up-to-date quarantine information by visiting the MDA Web site.”

Fortunately, there are many choices for replacement trees. What’s important is to diversify your plantings to avoid the potential devastating effects of a similar outbreak in the future.

“We’re pushing diversity as much as possible,” explains Smitley. “Don’t plant any two trees of the same type.”

To match specific trees to growing conditions, Smitley suggests MSU Bulletin E2925: “Recommended Alternatives to Ash Trees for Michigan’s Lower Peninsula.”

The EAB is a tiny beetle less than 3/4 of an inch long. It is believed to have been imported from Asia in wooden packing material, and lays its eggs under the bark of ash trees (even healthy trees). The developing EAB larva begins feeding on the cambium layer of the tree, which results in its eventual demise. About 15 million ash trees have been destroyed since the outbreak was discovered and the insect threatens over 700 million remaining ash trees in the state. The insect has also been discovered in Ohio, Indiana, and portions of southern Ontario.

To obtain the MSU bulletins or more information, visit one of these Web sites: www.emeraldashborer.info or www.michigan.gov/EAB.

Neil Moran is a horticulture instructor and author of “North Country Gardening: Simple Secrets to Successful Northern Gardening.”