为了实行害虫管理,必须有能够控制害虫密度的技术。在森林条件下,由于长期性经营条件的制约,自然控制要比直接密度控制更显得重要。使自然控制取得好的效果的技术,多数能得到长期的省力的效果。到目前为上,森林昆虫学还是认为林业防治法和森林卫生重要。林业防治法就是为造林、培育和收获森林,利用人为活动增加机会,把森林里的树种立地选定、林分构成配置、采伐更新等作为自然控制害虫容易起作用的条件。山口把这种条件调整分为种间关系 In order to implement pest management, there must be a technique that can control pest density. Under forest conditions, natural control is more important than direct density control due to the constraints of long-term operating conditions. Most of the technologies that bring good results to natural controls can achieve long-term, labor-saving results. Up to now, forest entomology still believes that forestry control law and forest health are important. Forestry prevention and control law is to afforestation, nurturing and harvesting forests, the use of human activities to increase opportunities for site selection of tree species in the forest, stand configuration, logging and updating as a natural control of pests easy to play a role. Yamaguchi to adjust the conditions divided into species relations