地膜下的杂草必须在覆膜前施用除草剂进行化学防除,防止其出土拱地膜。化学除草要求对杂草防除高效,而对蔬菜安全。由于蔬菜种类较多,一种蔬菜又有很多品种,每种蔬菜的栽培时间、栽培方式也有差异,且轮作倒茬频繁,间作套种普遍。要进行化学除草,必须严格选用化学除草剂。要根据蔬菜种类、品种、栽培时期、栽培方式、土质、管理方式等多种因素全面考虑,合理使用。同时,要求除草剂还要兼顾:选择性强,能对多种蔬菜安全,要求对当茬、后茬均要安全;杀草谱 Submerged weeds must be applied in the film before the chemical control of herbicides to prevent the excavated arches. Chemical weed control requires efficient weed control and is safe for vegetables. As more types of vegetables, there are many varieties of vegetables, cultivation of each vegetable time, cultivation methods are also different, and crop rotation frequently, intercropping common. Chemical weeding, we must strictly use chemical herbicides. According to the types of vegetables, varieties, cultivation period, cultivation methods, soil quality, management methods and other factors fully considered and rational use. At the same time, we must also take into account the herbicides: strong selectivity, can be a variety of vegetables, requiring stubble, stubble have to be safe;