松毛虫(Dendrolimus spectabi1is)是松类最主要的食叶性害虫,常给日本的赤松林、黑松林带来严重的危害,其严重性是人所共知的。然而,松毛虫的发生程度与松林受害程度的关系迄今并未为人们所了解。食叶性害虫所造成的食害,主要是受害林分(树木)叶量的减少而导致生长量的减退。要防治松毛虫,就必须对其栖息数→叶量减少→生长减退等一系列关系有 Dendrolimus spectabi1is, the most important leaf-eating pest of pine, often causes serious damage to the Japanese red pine and black pine forests. The severity of the disease is well known. However, the relationship between the occurrence of pine caterpillars and the degree of damage to pine forests has not been known to date. The food damage caused by leaf-eating pests is mainly due to the decrease of the amount of the leaves due to the decrease of the amount of the damaged leaves (trees). To control pine caterpillars, we must its habitat number → reduce the amount of leaf growth and a series of relationships such as decreased