Emerald Ash Borer


Ab​out​​ EAB

Emerald ash borer (EAB) is an invasive beetle native to northeastern Asia​ that attacks all species of ash (Fraxinus spp). First detected in the United States in 2002, EAB is thought to have been introduced from China in wood shipping crates. It was confirmed for the first time in Wisconsin in 2008 and has subsequently been detected in 71​​ of the state's 72 counties. DATCP expects EAB will eventually infest all parts of the state where ash trees occur. Currently, ash tree mortality and other impacts of EAB are most severe in the southern half of Wisconsin, while there are still northern areas where EAB has not yet been found.

Detections in Wisconsin

Reporting EAB

It is not necessary to report EAB in municipalities where it has already been detected. However, if you live in a county or municipality where we​ have not yet detected it, you should report it. To check your county’s detection status and report if necessary, visit our interactive map​ and enter your street address. 

Life Cycle and Damage

Adult EAB beetles are active in late spring and early summer. The adult females lay eggs on the bark of ash trees, and the flat and worm-like larvae hatch and burrow beneath the bark. The larvae kill trees by feeding on the wood immediately under the bark. This disrupts the capacity of the tree to take up water and nutrients from the roots and kills the tree from the top down. 


DATCP strongly recommends using only certified firewood, or that you buy firewood near where you will burn it. This is a best practice to slow the spread of EAB and prevent the introduction of new and potentially harmful forest pests and diseases. It is also important to remember there are restrictions on firewood movement due to spongy moth quarantine regulations. There are also rules for firewood use on state, federal, and Tribal lands in Wisconsin. Read more about moving firewood in Wisocnsin here

Federal Deregulation

In 2021, EAB was deregulated at the national level by the USDA Animal and Plant Health Inspection Service (APHIS), and Wisconsin's EAB quarantine rule was rescinded in 2023. When this regulation changed, some states west of Wisconsin, including Minnesota, took steps to enact exterior quarantines for EAB. The quarantine regulations restrict the movement of ash products such as logs, nursery stock, and/or firewood from Wisconsin to these states. Businesses and individuals should proactively check current plant regulations prior to shipment of any potentially regulated articles. To learn more, visit the State Law & Regulation Summaries: National Plant Board webpage. 

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