Non-native species encounter novel habitats and exhibit three distinct population processes: arrival, establishment, and dispersal. Arrival of the Asian Longhorned Beetle (ALB) outside its native range can be inferred by the location of conspicuous established populations; however, understanding establishment in novel landscapes where population densities are low and host availability is high remains relatively understudied due to the unperceived nature of these non-indigenous species. The tracking of ALB by examining all the trees, both infested and non-infested, allows us to describe an “establishment” event for ALB in a small, isolated population within the regulated quarantine zone of Worcester County, Massachusetts, USA.
Results/Conclusions
Seventy-one infested red maple (Acer rubrum) trees and 456 un-infested trees were surveyed. Dendrochronology of infested trees and location, species (when possible), and diameter at breast height (dbh) for all 527 trees were recorded. Tree ring analyses indicated that this population had recently established within four years prior to removal by the USDA. ALB initially infested one or two trees then moved through the understory canopy and infesting new trees based not on distance or direction but on tree size, with larger trees being preferred. ALB infested A. rubrum host trees were larger (median = 19.5 cm dbh) compared to un-infested A. rubrum (median = 7.8 cm dbh). Outside of this stand, surrounding survey data suggest long-distance dispersers may have emerged above the canopy and followed the direction of prevailing winds.