在北方的春玉米田，由於玉米播種時氣溫低，幹旱少雨
，為保證播後苗前土壤施藥有很 好的除草效果
，就必須澆足底墒水，精細整地，播後鎮壓
，然後施除草劑，如果土壤墒情不好，施藥後可淺混土(2～3厘米)huojinrupenguan，yitigaochucaoxiaoguo
，yeyouyushiyaoshidiwenshaoyu，erqielihouchadexiaomaibozhongqijiangejiaochang

，keyiantuijianyongyaoliangdeshangxianshiyaohuoshidangjiadayongyaoliang，yibaozhengyoujiaogaodechucaoxiaoguo。

    華北地區的夏玉米一般是5月下旬至6月上、中旬播種，這時已進入夏季，氣溫高，降雨 duo，zacaochumiaoshengchangkuai
，rubujishifangchu，rongyizaochengcaohuangyinqijianchan，huaxuechucaoyingyibohoumiaoqianturangchuliweizhu。youyuxiayumibozhongqiyuhouchazuowuxiaomaidebozhongqijiangejiaoduan，xuanyongchucaojiyingzhuyiduihouchazuowuxiaomaideyingxiang，liruyouqujinshiyumitianchangyongdechucaojizhiyi
，dantianjianchixiaoqihenchang，ruoyongyaoliangguodahuoshiyaobujunyun
，yiduihouchazuowuxiaomaizaochengcanliuyaohai
，youqujincanxiaoqidechangduanshouxuduoyinsudezongheyingxiang，erdanweimianjideshiyaoliangshiguanjianyinsu，youhuaqingyongyaoliangda，turangzhongcanliudeyaojijiuduo，turangzhongyouqujinhanliangdayu0.1毫克/千克時即影響小麥的萌發與生長

，莠去津的人解速度與噴藥均勻程度
、土壤質地、降雨量、土壤PH等因素有磁，研究表明
，華北地區夏玉米每分頃施38％莠去津膠懸劑3000毫升為臨界值，超過這個用藥量，就容易對後茬作物小麥產生藥害，各地可根據當地條件靈活掌握恰當的用藥量
，而玉米寶、40％乙莠水懸浮劑、50％hebaoruyoudengshiduiyumihehouchazuowudouanquandegaoxiaoguangpuchucaoji，youyuxiayumibozhongqiqiwengao，jiangyuduo，liyuchucaojiyaoxiaofahui，keyongtuijianyaoliangdexiaxianhuoshidangjiangdiyongyaoliang，yenengyidejiaogaodechucaoxiaoguo。