落叶松枯梢病是我国东北地区落叶松人工林普遍发生而且危害严重的一种毁灭性真菌病害。该病害蔓延迅速,仅我省就由1978年的26万亩扩大到1983年的50万亩,被害面积占落叶松总面积的20%。全省每年损失木材约6万立方米。为了尽快解决防治问题,我们于1978-1983年利用化学药剂进行小试、中试和大面积推广应用,取得了较好的防治效果,现将试验结果分述如下: 一、小试结果1978-1980年在丹东、本溪两地区的六个国营林场用39种药剂进行试验,筛选出11种防 Larch blight is a devastating fungal disease that occurs most commonly in Larch plantations in northeastern China. The rapid spread of the disease, only in our province from 26 million mu in 1978 expanded to 500,000 mu in 1983, the victim area accounted for 20% of the total area of ​​larch. The province lost about 60,000 cubic meters of timber each year. In order to solve the problem of prevention and treatment as soon as possible, we use chemical reagents for small-scale, pilot-scale and large-scale popularization and application in 1978-1983 and achieved good control effects. The test results are described as follows: In 1980, six state-owned forest farms in Dandong and Benxi districts were tested with 39 kinds of pesticides, and 11 kinds of pesticides were screened