Emerald Ash Borer Discovery in Wisconsin

In early April the emerald ash borer was discovered near Victory, WI just across the Mississippi River from the Iowa-Minnesota border. [news release]

The emerald ash borer (EAB) is a small, invasive beetle, whose larvae tunnel under the bark, killing ash trees. With the discovery of an EAB infestation within sight of Iowa there is a great deal of concern about what this means for ash trees in Iowa.

The following is a brief summary of what is known and what is planned for the next few months in Iowa.

First, no EAB infestations have been found in Iowa through ongoing surveys, including tree inspections in Allamakee County across from Victory WI as recently as last week.

Background information on the Victory, Wisconsin EAB infestation

  • The infestation was reported by a citizen who phoned the Wisconsin EAB hotline on March 30, 2009, reporting dead/dying ash in the area. A County Forester looked at the trees, took pictures and forwarded them to state officials. State officials visited the site on April 3, found larvae and sent them to a federal identifier. Positive confirmation was made Monday, April 6, 2009.
  • Victory WI is a very small, unincorporated town on the banks of the Mississippi River. Ash trees in and near this town are infested with EAB.
  • Wisconsin officials have confirmed that the Victory EAB infestation extends 2.5 miles south of town. They are continuing survey work but it may be some time before we know how far this infestation extends into Wisconsin because the area is heavily wooded and consists of rolling hills and river bottom land.
  • Vernon County becomes the fifth infested county in Wisconsin. Crawford County has also been quarantined because of close proximity to the Victory infestation. EAB was discovered in Ozaukee and Washington counties last summer (2008); adjacent Fond du Lac and Sheboygan counties were also quarantined.

Emerald Ash Borer and Iowa

  • There is no confirmed EAB infestation in Iowa as of April 23, 2009. In addition EAB has not yet been found in Minnesota.
  • For the update on where EAB has been found in Iowa, see https://hortnews.extension.iastate.edu/emerald-ash-borer
  • USDA and other officials have visually assessed trees in high risk areas in Allamakee Co. and cut down and peeled the bark of suspect trees. No EAB infestations were found in Iowa.
  • DNR estimates there are up to 5 million ash trees in Allamakee County, comprising about 5% of the trees in the forested areas of this county. Allamakee is the most forested county in Iowa with 42% of the land covered by trees (176,000 acres of forest).
  • The impact of EAB will be devastating. The cost of removing and replacing destroyed trees will be financially taxing, and the loss of such a large amount of trees will cause a severe environmental impact as well. There are approximately 88 million ash trees in Iowa, many of them in cities and neighborhoods. Loss of these ash trees may very well increase heating, cooling, and watering costs for residential areas. Iowa estimates the cost from EAB will exceed $7.5 billion to remove dead trees and another $5 billion to replant.
  • The Iowa Department of Agriculture and Land Stewardship, Iowa Department of Natural Resources, and Iowa State University Extension, in cooperation with USDA-APHIS and USDA Forest Service have been working together for several years surveying Iowa for EAB using visual assessments, purple sticky traps, and sentinel (‘trap’) trees. To date none of these EAB survey tools has indicated any infestation within Iowa. State and federal officials are now planning the survey for the coming summer.
  • Iowa State University Extension has begun work on control recommendations specific to Iowa home and landowners. However, no treatments are recommended in Iowa at this time.

Tri-State Plans

  • Because of the proximity to property managed by state and federal entities and the short distance to counties in Iowa and Minnesota, development of an area-specific response plan with multiple partners is in the making for the "three corners" area.
  • One of the first steps in responding to the infestation will be to quarantine movement of hardwood firewood, ash nursery stock, ash timber or any other article that could spread EAB out of the infested area in Wisconsin. Minnesota has announced a state emergency quarantine of Houston Co. although they have not yet confirmed an EAB infestation in the state.
  • We are preparing to ramp up our educational activities on EAB. These will be in addition to the previous emerald ash borer presentations, video broadcasts and web sites developed by Dr. Mark Shour, ISU Extension Entomologist, and Tivon Feely, Iowa DNR Forest Health Specialist. This will include a special program called "First Detector Training" authorized and funded in part by grants from the National Plant Diagnostic Network for dealing with invasive species.

Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Horticulture and Home Pest News, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on April 22, 2009. The information contained within may not be the most current and accurate depending on when it is accessed.