Emerald Ash Borer

The Emerald ash borer (Agrilus planipennis), an invasive, wood-boring beetle that attacks ash trees, was positively identified for the first time in Wisconsin in August 2008. The beetle and beetle larvae were found at a private home in Ozaukee County, Wisconsin.

For current information on emerald ash borer in Wisconsin please visit the Wisconsin Emerald Ash Borer Information Source.  Here you will find detailed information on emerald ash borer biology and host preference, firewood and quarantine regulations, management options and information on what Wisconsin is doing about emerald ash borer.

Introduction

The emerald ash borer (Agrilus planipennis), an invasive, wood-boring beetle that attacks ash trees, was positively identified for the first time in Wisconsin in Ozaukee and Washington Counties in August 2008. Since then, a second infestation has been identified in Vernon County in April 2009.  This exotic insect, native to Asia, was first detected in North American in Detroit, Michigan in 2002.  Since this initial detection, the emerald ash borer has killed tens of millions of ash trees (Fraxinus spp.) in the Great Lakes region and beyond (see distribution map).

Emerald Ash Borer's Effects

The emerald ash borer belongs to a group of insects known as metallic wood-boring beetles (Buprestidae). The beetle's immature or larval form spends its life feeding beneath the bark of ash trees. As a result, the ash tree host suffers extensive damage to its vascular system, depriving the tree's crown of water and nutrients. Research conducted by Michigan State University and the USDA Forest Service has shown the emerald ash borer attacks both stressed and healthy ash trees, typically killing its host in three to five years. All ash species in Wisconsin are attacked, including white, green black and blue ash. Mountain ash (Sorbus spp.), not a true ash, is unaffected.

Emerald Ash Borer Spreads Through Firewood

Emerald ash borer is a slow-moving insect, dispersing just one-half to two miles annually on its own. However, this rate of dispersal can be greatly accelerated by humans transporting ash firewood, nursery stock and other wood products long distances. This inadvertent transportation of emerald ash borer larvae in infested materials by people has greatly increased the distribution of emerald ash borer across the country (see distribution map). Since the detection of emerald ash borer, firewood and quarantine regulations have been put in place to try to slow the spread of this pest.

We Need Your Help

Forest inventory and analysis data shows that Wisconsin's forests include approximately 757 million ash trees. As a component of our northern hardwood, oak-hickory and bottomland hardwood forests, ash trees are a valuable Wisconsin resource. In addition, an estimated 5.2 million ash trees are planted throughout the urban landscape. The potential destruction that emerald ash borer could bring to Wisconsin is unfathomable. As of April 2009, the emerald ash borer has only been found in two locations in our state, but it is very likely present elsewhere.

Early detection and isolation of infestations are our best defenses against the ecological and economic damage caused by emerald ash borer.
The development of the Wisconsin Emerald Ash Borer Response Plan [PDF, 350KB] and the more comprehensive Strategic Plan for Emerald Ash Borer Program Activities [exit DNR] has been completed by the State of Wisconsin Emerald Ash Borer Advisory Group. The Advisory Group is a collaborative effort between the Wisconsin Department of Natural Resources (WI DNR), Wisconsin Department of Agriculture, Trade and Consumer Protection (DATCP), University of Wisconsin, UW-Extension, USDA-APHIS and USDA-Forest Service. Despite this large interagency effort fronting the fight against emerald ash borer, we still need your help looking for emerald ash borer due to the elusive behavior of this pest!

Please review the information on EAB signs and symptoms, other pests and diseases and EAB look-alikes on this website. After that, if you still suspect an emerald ash borer, please report it immediately by calling the emerald ash borer hotline at 1-800-462-2803 or report online.