Forests are the highest ranked land cover type in Europe. Numbering at around 40% of the total land area, they provide numerous goods and services of benefit to people. These include, not only marketed products such as wood, but also ecosystem services of great value from an ecological, political, social and cultural perspective. Among the latter are water resource management, preservation of biodiversity, climate change mitigation, recreation and health benefits, cultural heritage and protection from soil erosion.
In the last decades, a growing list of introduced non-native pests and pathogens (PnPs) have been causing dramatic losses to European trees and forests. Most of these devastating PnPs, e.g. chestnut blight, ash dieback, Asian long-horned beetle and western conifer seed bug, were harmless or even unknown in their region of origin. The exponential rates of introduction and establishment of non-native PnPs in Europe are clearly linked to increasing global trade.