Emerald ash borer (Agrilus planipennis Fairmaire) populations are expanding naturally and through artificial transport of infested ash material. Additional populations of emerald ash borer (EAB) will undoubtedly continue to be discovered. When a localized outlier site is found, there are currently few options to manage EAB or mitigate damage. Eradication efforts attempted in the first few years after EAB was discovered were expensive and generally had a poor record of success. Regulations imposed to limit transport of ash nursery trees, logs, firewood and related items from infested areas should reduce artificial dispersal of EAB. Regulatory efforts alone, however, do little to alter the increase and spread of EAB populations and the subsequent onset and progression of ash mortality.
The rate at which ash tree mortality advances is related to EAB density. Therefore, an over-riding theme within the SLAM approach is to reduce EAB numbers and the growth of EAB populations. This can occur by destroying EAB life stages before adults can disperse and reproduce, concentrating and eliminating adult beetles and their progeny, and reducing the amount of food (ash phloem) available for the development of large numbers of EAB offspring. As outlier populations build and coalesce, the area encompassing dead, dying and declining ash trees increases dramatically. A do-nothing or a regulation-only approach means that EAB populations will build and advance unchecked. Under that scenario, extensive local tree mortality is likely to occur much sooner than under a SLAM management scenario
Applying a SLAM approach will not eradicate EAB, nor will it eliminate tree mortality. The goal of this management strategy is to slow the local invasion process and allow land managers time to be proactive rather than simply reacting to overwhelming numbers of dead, often hazardous trees. When EAB was first identified in North America in 2002, little information about this beetle was available. Tools available for EAB survey and control have progressed considerably. Continued research and methods development will yield more options for EAB management and increase the effectiveness of existing technologies. Slowing the movement of EAB and the advance of ash mortality buys time for research and technology development.