Ecological, evolutionary, and societal impacts of invasions by emergent forest pathogens

Inexplicably, the review literature on biological invasions has often omitted those by plant pathogens. Here, we provide a review on the consequences of invasions by forest pathogens, whether non-native and introduced or native and invasive due to ecosystem-level alterations such as those caused by climate change, practices associated with forestry, and the planting of exotic hosts. Together, these two classes of invasive pathogens can be defined as emergent and can lead to the rise of novel plant diseases causing detrimental effects on affected ecosystems. This chapter will present examples of such detrimental effects with a focus that goes beyond the mortality of the main host plants, by including ecosystem-level, evolutionary, economic, and societal impacts associated with disease outbreaks caused by emergent tree pathogens.