Forest Insect Invasions and Their Management

Abstract

AbstractAs a result of increasing globalization, hundreds of forest insect species have been accidentally transported among continents. The most common invasion pathways by which non-native forest insects are transported globally are wood packaging material and live plants. While most non-native forest insect species have no noticeable impacts in their non-native ranges, several species have had serious or even catastrophic effects on tree health, forest resources and ecosystem functions. Approaches to preventing and managing forest insect invasions correspond to the four phases of biological invasions: arrival, establishment, spread and widespread established populations. Biosecurity agencies manage arrival through commodity entry prohibitions, port inspections and mandatory phytosanitary procedures designed to reduce transport of non-native species. Biosecurity measures to prevent establishment focus on surveillance (e.g. traps) to detect new populations that sometimes can be eradicated if populations are discovered early and their occurrence is limited. In very few cases, spread of invasions may be slowed or stopped using containment or barrier zone management. Finally, once populations are established and widespread, methods such as biological control, host resistance breeding, silviculture and pesticides may be needed to mitigate damage caused by non-native pests. As the world becomes increasing interconnected, more insect species are likely to become established in new regions, further increasing the problems associated with non-native forest pests.