The Japanese pine sawyer,Monochamus alternatusHope (Coleoptera: Cerambycidae), is the key factor in the subsequentBursaphelenchus xylophilusdistribution and dispersal from wilt-killed to healthy pines during maturation feeding and oviposition. Therefore, effective monitoring ofM. alternatuspopulations is needed for the surveillance of pinewood nematode disease in infected or noninfected areas. The results presented here involved the seasonal variations ofM. alternatusadults and other major Coleoptera in pine forests from 2011 to 2012 in the Xiaoshan District, which is surrounded byB. xylophilus-infected areas, in Zhejiang Province, Eastern China.M. alternatusadults occurred at one generation per year, and the active period for adults lasts from middle-May to early-September, with peak numbers recorded in late-June. The data indicated that the population density ofM. alternatusin the investigated forests is very low. However, bark beetles and pine weevils at a high-density level, were active and emerged earlier thanM. alternatus. We suggest that a high alert level must be maintained regarding the damage of bark beetles or pine weevils, which might lead to the facilitation ofB. xylophilusinvasion process. [ABSTRACT FROM PUBLISHER]