The average population density is above 118 in the forest stand that robur can account for 90% , and 50 in a forest stand that robur account for 40% .

• 虫口密度与林分组成的关系为栎树纯林和栎树比例在9以上的林分平均虫口在118头／株以上,危害重;而栎树比例在4以下的林分平均虫口在50头／株以上,危害轻。