Abstract
Trap-nests are useful tools to monitor solitary bees and wasps that nest in tube-like cavities. We installed trapnests made from internode tubes of bamboos and reeds in ten secondary deciduous broad-leaved stands of different ages of one to over 100 years after clear-cutting. Thirty-two species (eight families of Hymenoptera and one of Diptera) were obtained with the trap-nests: 20 host species and 12 of their natural enemies. The species richness of most families of hosts and natural enemies, except for Pompilidae, was higher in younger to middle-aged stands than in older ones over 70 years old. On the contrary, the family Pompilidae (spider wasps) proliferated in both young and old stands, with its relative abundance becoming greater with the increase in stand age.
