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我县位于北纬41°35′—42°40′,东径116°32′—118°14′,在河北省的最北部,地势西北高东南低,分为坝上高原和坝下山区两部分,海拔750—2021米,无霜期60—120天,年平均气温5℃,年降雨量419.9毫米。全县现有林481万亩(机械林场102万亩,孟滦林管局122.6万亩,牧场19万亩,集体林233.9万亩)。在社队集体林中有落叶松、油松林70余万亩。 当前,松林的主要虫害之一是落叶松毛虫Dendrolimus superaus(Butler),别名西伯利亚松毛虫,简称松毛虫。早在1961年即
My county is located at latitude 41 ° 35’-42 ° 40 ’and 116 ° 32’-118 ° 14’ east longitude. In the northernmost part of Hebei Province, the county is located in the lower southeast of the northwestern part of the province and is divided into two parts: the dam plateau and the dam under the dam , 750-2021 meters above sea level, frost-free period of 60-120 days, the annual average temperature of 5 ℃, the annual rainfall of 419.9 mm. The existing county forest 4810000 mus (mechanical forest 1020000 mus, Mengluan forestry bureau 1226000 mus, pasture 190000 mus, collective forest 233.9 mus). In the community collective forest larch, pine forest more than 70 acres. Currently, one of the major pests of pine forests is Dendrolimus superaus (Butler), also known as Dendrolimus sibirica, referred to as the pine caterpillars. As early as 1961