Department of Entomology

Since the discovery of the Emerald Ash Borer (EAB) in Wisconsin in 2008, the infestation has curiously been fairly quiet.  While EAB has been found in the greater Milwaukee area, Brown County, and along the Mississippi, the infestations have been slow to move out of those areas.  For a few years, the old saying, “no news is good news” seemed to be holding true.  

Recently, however, EAB has been getting quite a lot of attention in the news.  Several new finds have been reported in the state, and it’s hard to tell exactly when or where EAB will strike next.  Could this be the year EAB reveals itself throughout Wisconsin?  It’s possible.  However, a few historical and geographic details can help show that the recent finds aren’t entirely surprising:

• The EAB infestation near Detroit (the first major metropolitan area to deal with EAB) radiated outwards from a central infestation over several years.      
• Most of the EAB reports in the news this summer focus on areas either in or just outside of the greater Milwaukee or Chicago areas.  EAB had first been discovered in the greater Chicago area in 2006, and in the greater Milwaukee area in 2008.
• So far, the new EAB finds for 2012 are in counties that had already been quarantined, or are directly adjacent to an infested county.
• In their initial stages, EAB infestations can be extremely difficult to identify.  Thus, an infestation may build up for several years before it is identified.   

Although the news reports may make it seem that EAB is moving fast this year, what we’re seeing so far in 2012 may just be the natural progression of this insect.

Unfortunately, EAB hasn’t shown any signs of slowing down or stopping, so all Wisconsinites should be prepared to face this destructive pest at some point.  Luckily, many residents of the state have already heard about EAB and are aware of the issue thanks to the educational outreach effort of the University of Wisconsin Extension educators.  Many cities and towns have had EAB on their radar for some time and have developed management plans for their urban forests.  Chris Williamson, Phil Pellitteri, and myself have been involved with EAB Extension activities since 2005 and have been able to reach thousands through seminars and the Entomology Department’s emerald ash borer website.  We’ve recently revamped the EAB website to have updated information on the biology and management of EAB as well as a brief glimpse into EAB research going on at UW-Madison. 

The UW-Madison emerald ash borer website can be found at:  http://www.entomology.wisc.edu/emeraldashborer/ 

---P.J. Liesch

UW-Madison Entomology Department