Adult emerald ash borer (Agrilus planipennis), a major introduced pest of ash trees. While the adult form does minor damage to ash foliage, the larvae live within the wood, eating the inner bark and disrupting the transport of water and nutrients, killing the tree. Emerald Ash Borers, or EABs, have killed tens of millions of ash trees in an expanding circle around the Great Lakes, where it is believed they arrived in solid wood packing materials from Asia.