Emerald Ash Borer Treatment Options Recently Revised

Extension publication outlines new treatment options

March 26, 2015, 9:39 am | Mark Shour, Laura Jesse Iles

Emerald Ash Borer PublicationAMES, Iowa — The four-page Emerald Ash Borer Management Options, PM 2084, has been revised and is available from Iowa State University Extension and Outreach as a free download. The publication provides recommendations on how to protect ash trees from the emerald ash borer. Information about the life stages affected by systemic insecticides, two new professional products and proper use to protect insect pollinators has been added to the publication. It also highlights two pesticides that protect the ash tree for two years.

Properly applied systemic insecticides provide effective and consistent protection against the emerald ash borer. Ash trees within 15 miles of a confirmed emerald ash borer infestation are at risk of attack. Ash trees outside the risk zone should be monitored for emerald ash borer symptoms.

“The best way to protect ash trees from the emerald ash borer is to treat the trees before they are infested,” said ISU Extension and Outreach Entomologist Mark Shour, one of the publication’s authors. Infested trees with less than 30 percent dieback of the crown due to emerald ash borer feeding may recover following treatment.

“If you live within 15 miles of the known infestations and are willing to make a long-term commitment to caring for your ash trees, then using one of the registered products is warranted. If you are not in a known infested area, treatment may be premature,” Shour said. “In general, spring is the best time of the year to treat for emerald ash borer.”

The publication gives recommendations for homeowner and professional treatments. “If your tree’s diameter (measured on the trunk 4.5 feet above the base) is 20 inches or smaller, a homeowner treatment method is a good solution for controlling EAB,” said Shour. Trees larger than this size must be treated by a certified pesticide applicator holding a current Category 3O (Ornamental Pest) or 3OT (Ornamental and Turf Pests) certification with the Iowa Department of Agriculture and Land Stewardship.

As of March 25, 2015, emerald ash borer infestations have been positively identified in 20 Iowa counties: Allamakee, Appanoose, Black Hawk, Boone, Bremer, Cedar, Clinton, Des Moines, Henry, Jasper, Jefferson, Keokuk, Lucas, Mahaska, Marion, Monroe, Muscatine, Story, Union and Wapello counties.

A statewide quarantine, issued on Feb. 4, 2014, restricts the movement of hardwood firewood, ash logs, wood chips and ash tree nursery stock out of Iowa into non-quarantined areas of other states.

Adult Emerald Ash BorerAgrilus planipennis is an exotic beetle commonly called Emerald Ash Borer and is native to eastern Asia. It was first detected in the United States near Detroit, Mich., in 2002. Emerald ash borer kills all ash trees by larval burrowing under the bark and eating the actively growing layers of the cambium.

Photo: Adult Emerald Ash Borer

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