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１９９３～１９９５年在牙克石林区研究了两年一代落叶松毛虫的发生期与物候和二十四节气的相关性；发生量与５月份温雨系数和幼虫越冬后排粪量的相关性；建立了以温雨系数ｘ１、排粪量ｘ２为自变量，发生量为因变量ｙ的回归估测模型：ｙ∧＝１９６．２６８０－２３．５１７０ｘ１，ｙ∧小虫＝２．４４９９＋０．０７３２ｘ２，ｙ∧大虫＝１１．９７００＋０．０２７８ｘ２，兴安落叶松的失叶量超过４５％，对其高、胸径及材积生长有显著影响。在５月中旬前，当有虫株率超过４０％，大虫虫口密度超过５０头／株，小虫虫口密度超过１０１头／株时，必须防治。
The correlation between the occurrence of two-year-old Dendrolimus caterpillars and phenology and twenty-four solar terms was studied in Yakeshi Forest Region from 1993 to 1995. The correlation between the occurrence of the two-year- The regression model was established with the temperature coefficient x1 and the amount of defecation x2 as the independent variable and y as the dependent variable y: y ∧ = 196.2680-23.5170x1, y ∧ insects = 2.4499 + 0.0732x2, Larvae y = 11.9700 + 0.0278x2, Larch Larix more than 45%, its height, DBH and volume growth have a significant impact. Before mid-May, prevention and control of pests should be given when the rate of pests exceeds 40%, the population density of pests exceeds 50 pests per plant, and the population density of bugs exceeds 101 pests per plant.