The emerald ash borer (EAB) is not infesting Iowa yet, although presence of the insect has been confirmed in adjoining states. ISU Extension, state regulatory agencies and local officials continue to monitor the situation in Iowa. In the meantime, Iowans can turn to a new ISU Extension publication for options to help them protect their ash trees from this invasive insect.
“Emerald Ash Borer Management Options” (PM 2084) offers recommendations for homeowners and commercial pesticide applicators on products that can be used to protect healthy ash trees from EAB attack. Mark Shour, an ISU Extension entomologist who is the lead author on the publication, said treatment is most effective before the adult stage finds the ash tree. EAB adults are active from May until August.
EAB will destroy ash trees, but treatment of trees isn’t recommended until the insect has been positively identified 15 to 20 miles away, Shour noted. The adult borer causes minor feeding damage to ash foliage. The larval stage feeds beneath the bark, disrupting water and nutrient flow within the tree, eventually killing it.
EAB is a concern because of the potential financial and environmental impacts. Iowa has approximately 88 million ash trees, many of them in cities and neighborhoods. Loss of these ash trees would likely increase heating, cooling and watering costs for residential areas. The Iowa Department of Natural Resources estimates the cost from EAB could exceed $5 billion.
PM 2084 is available from the ISU Extension online store. (Download a pdf file or order a print copy.) Additional resources for dealing with EAB are available from ISU Extension’s Pest Management and the Environment Web site.