Emerald Ash Borer (EAB) was found in Boulder, CO, in September 2013. As a non-native insect, EAB lacks predators to keep it in check. EAB only attacks ash trees in the genus Fraxinus (so mountain ash are not susceptible). EAB is responsible for the death of millions of ash trees in the Midwest. Help protect Colorado's ash trees! Don't move firewood, and consider chemical treatments to protect high-value ash trees.