Concluding remarks

Abstract

The Japanese pine sawyer, Monochamus alternatus, the vector of PWN is native to Japan and East Asia. Originally, M. alternatus lived on weakened or dead pines such as dead branches or suppressed trees, and did not kill pine trees. In the past its natural population levels were far lower than today and it was a rare insect species before the PWN was introduced into Japan. Before then the population levels of the pine sawyer were limited mainly by the amount of available food, weakened trees, and thus, the importance of natural enemies was low. © 2008 Springer.