This thesis, presented in four chapters, focuses on differences in forest vegetation, black ash (Fraxinus nigra) dendroecology across 24 black ash stands, and longhorn beetle (Coleoptera: Cerambycidae) species assemblages across eight stands, representing different stages of the emerald ash borer (EAB) (Agrilus planipennis Fairmaire) invasion referred to as: Post-, Mid-, and Pre-Invasion stands. Chapter one consists of a comprehensive assessment of forest vegetation across EAB Invasion Strata. Post-Invasion stands in the Lower Peninsula and eastern Upper Peninsula have experienced extensive overstory black ash mortality and Mid-Invasion stands have experienced some black ash mortality, while black ash in Pre-Invasion stands were predominately healthy. Black ash recruits (trees DBH 2.5-10 cm) in Post-Invasion stands exhibited high rates of mortality, and many recruits in Post- and Mid-Invasion stands were infested with EAB larvae. Chapter two focuses on the dendroecology of black ash overstory trees and recruits in 24 stands. Age of black ash recruits also varied but one recruit was 98 years old. In Post-Invasion stands, increases in annual ring width following overstory black ash mortality indicated release of black ash recruits. Chapter three examines cerambycid beetle species assemblages in eight black ash stands in Michigan’s Upper Peninsula, in stands representing Mid and Pre-Invasion conditions. We recorded 43 new county records for 22 species of cerambycids and captured two species not previously reported from the Upper Peninsula. Finally, chapter four presents results from a 15-year common garden study in which survival and EAB infestations were tracked for four North American ash species: black ash, blue ash (Fraxinus quadrangulata), green ash (Fraxinus pennsylvanica), and white ash (Fraxinus americana), along with two Asian ash species: Chinese ash (Fraxinus chinensis) and Manchurian ash (Fraxinus mandshurica).
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