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黄褐天幕毛虫在东北地区一年一代，分龄期记录幼虫食叶面积，根据杨树人工林的受害阈限为失叶40％，计算出每平方米面积食叶40％的老龄幼虫数，17条／m2为危害指标。
On a year-old generation in Northeast China, yellow-brown caterpillars recorded larvae leaf area in different age groups. Based on the damage threshold of poplar plantations of 40% of leaf loss, the number of aged larvae per square meter of leaf area was calculated to be 40% 17 / m2 as a hazard indicator.