4H-3,1-Benzoxazine derivatives of the formula ##STR1## where R.sup.1, R.sup.2 and Y have the meanings given in the specification, and their use for controlling unwanted plant growth in numerous crops, such as cereals, Indian corn, soybeans and cotton.
4H-3,1-苯并噁嗪的衍
生物的
化学式为 ##STR1## 其中R.sup.1,R.sup.2和Y的含义如规范中所述,并且它们可用于控制多种作物中不需要的植物生长,例如谷物,印第安玉米,大豆和棉花。