杂草危害直接造成果树产量损失一般在20%左右,我国大型果园除草用工仅次于病虫害防治,约占果树作业总用工量的三分之一。有的果园全年除草4-5次,雨季还常出现草荒。化学除草比人工或机械除草有明显优越性,是现代化农业的主要标志。1979年以来我所开展化学除草试验研究,今对北方 Weed damage directly caused by the loss of fruit production is generally about 20%, China’s large-scale orchard weeding workers only after pest control, accounting for about one-third of the total fruit tree work. Some orchards 4-5 times the annual weeding, rainy season often appear grass shortage. Chemical weeding than artificial or mechanical weeding has obvious advantages, is the main symbol of modern agriculture. Since 1979, I conducted chemical weeding experimental research, to the north