The emerald ash borer (EAB) is an exotic forest pest that has killed millions of ash trees in the
United States and Canada, resulting in an ecological disaster and billions of dollars in economic
losses of urban landscape and forest trees. The beetle was first detected in Michigan in 2002 and
has spread through much of the Eastern and Midwestern U.S., reaching Minnesota in 2009. Since then, it has spread across the state and poses a great risk to the more than 1 billion ash trees in
Minnesota. The larval stage of EAB creates wounds on trees as they feed on the inner bark, causing disruption of water and sap flow that results in tree death. The fungal community associated with EAB larval galleries is poorly understood and the role these fungi may play in tree death is not known. This study describes fungi isolated from EAB larval galleries sampled throughout the main geographic areas of Minnesota where ash is affected by EAB. The results
identify important fungal functional guilds that are occupying a new niche in ash trees resulting
from EAB and include fungi that may accelerate decline in tree health, increase hazard tree
situations, or may provide options for biological control of this destructive invasive insect.