Cold Mortality of Emerald Ash Borer. Emily Johnson. Emerald Ash Borer. Accidental introduction Asian origin First discovered in 2002 and has spread since Death of millions of ash trees In the epicenter of invasion in MI, more than 99% ash mortality. As of this month, where are they?.
Scientists from the University of Minnesota claim that the extreme cold from the polar vortex (1/1/2014-1/9/2014) may delay spread of EAB and cause high levels of mortality