Canada is a world leader in biological control research. Reporting the status of biocontrol agents released in Canada over the last decade, this book presents case studies by target pest that evaluate the impact of biocontrol and recommend future priorities. In addition to a new chapter on future targets and an appendix listing established agents, this edition contains information of interest to a global audience, and chapters that address effects of invasive species and climate change.

The Sirex woodwasp, Sirex noctilio, is the most important invasive alien insect pest of Pinus plantations in the Southern Hemisphere. It now also threatens pines in North America. This book brings together the worldwide knowledge of researchers from Universities and Government institutions, as well as forest industry practitioners that have worked on the pest. Importantly, it is the first comprehensive treatment of the subject since S. noctilio was discovered outside its native range around 1900. The book covers all aspects of the biology and management of S. noctilio, including aspects of the insects’ taxonomy, general life history, host-plant relationships, population dynamics, chemical ecology and symbiosis with the fungus Amylostereum areolatum. The book also contains a comprehensive synthesis of the history and current status of the pest and worldwide efforts to control it, including biological control, silviculture and quarantine.

This text discusses advances in bark beetle and pathogen systematics; environmental and host factors predisposing trees to bark beetle or pathogen colonization; mechanism of interaction between bark beetles and pathogens; effects on trees and forest ecosystems; and management strategies.

Bark beetles and their associated fungi are among the greatest natural threats to conifers worldwide, but the degree to which host stored resources influence tree-beetle-fungal interactions has not been investigated. In western North America, the range of the mountain pine beetle (Dendroctonus ponderosae) has expanded from lower elevation Pinus contorta (lodgepole pine) forests into high elevation Pinus albicaulis (whitebark pine), a presumed superior host. I investigated whether stored resources in tree sapwood change after D. ponderosae attack, and whether this change relates to fungal colonization and beetle performance. I also studied how phloem and sapwood resources vary with elevation and tree diameter and examined the effect of tree species and diameter on D. ponderosae host selection. Following beetle attack and fungal colonization, sapwood non-structural carbohydrates (NSC), lipids, and phosphorus declined in attacked trees relative to un-attacked trees. Resource declines were related to the degree of fungal colonization, suggesting a direct benefit to fungi in both host species. In P. contorta, beetle performance was also positively related to stored resources. The concentration of stored resources was generally higher in P. albicaulis than in P. contorta and increased with elevation and tree diameter, suggesting a potential increase in host quality for D. ponderosae and/or fungi. Beetles preferred larger diameter hosts, and although stored resources did not affect beetle performance in P. albicaulis, beetles were more likely to attack P. albicaulis even when larger P. contorta were available. In a parallel system in Norway, phloem NSC and sapwood lipids also declined in Picea abies trees inoculated with the fungus Ceratocystis polonica relative to trees attacked by the bark beetle Ips typographus (which vectors C. polonica) or control trees, again indicating that stored resources enhance fungal colonization. Overall, my results suggest that host stored resources influence the interaction between bark beetles, fungi, and conifers primarily by enhancing fungal growth. Fungal access to stored resources may also benefit beetles in some host tree species. A better understanding of the trophic interactions between beetles, fungi, and conifers may improve our ability to predict bark beetle dynamics and range expansion.