Silvicultural options to reduce pine susceptibility to attack by a newly detected invasive species, Sirex noctilio

A normative woodwasp of Eurasian origin, Sirex noctilio F., was defected recently in Oswego, New York, infesting Scots, red, and white pine. S. noctilio has caused periodic widespread losses of pine timber resources in several Southern Hemisphere countries and may cause significant damage in pure even-aged stands and overstocked plantations in North America. However, stand management and biological control programs have successfully managed S. noctilio populations in other countries and similar programs are being developed for North America. Until the primary biological control agent, Beddingia siricidicola, a parasitic nematode, is established in North America, forest owners will have to rely solely on silvicultural treatments to reduce the susceptibility of at-risk pine stands to S. noctilio attack. Silvicultural treatments including precommercial thinning, promoting optimal growing conditions for pines on a given site, reducing numbers of susceptible hosts, and consistent monitoring of stands are suggested activities to help protect pine stands from invasion by S. noctilio.