The ability of natural enemies to control the pests in Arboretum which is in suburb and better management level are the strongest and can cut down the pests species amount effectively.

• 捕食性天敌在时间上能有效跟随害虫并控制其危害。地处市郊、管护措施较好的植物园天敌昆虫对害虫的控制能力最强，能有效地减少害虫的种群数量。