Sulfonylurea herbicides are weakly acidic compounds, and their leaching and degradation rates in soil are greatly affected by soil pH. The leaching ability increases with the increase of soil pH value; In acidic soil, the degradation rate is fast, while in alkaline soil, the degradation rate is slow. Sulfonylurea herbicides have extremely high activity and low application rates, requiring only a few grams to tens of grams per hectare, and are known as highly efficient herbicides. This type of herbicide can effectively control broad-leaved weeds, and some herbicides also have inhibitory effects on grass weeds, even very effective. Most sulfonylurea herbicides, such as sulfometuron methyl, sulfometuron green, sulfometuron methyl, sulfometuron methyl, sulfometuron methyl, sulfometuron methyl, sulfometuron methyl, and sulfometuron methyl, can be used as both pre - and post seedling treatment agents (in the early stage after weed emergence). Some sulfonylurea herbicides, such as sulfometuron methyl and broad-leaved powder, can only be used as stem and leaf treatment agents, and their effectiveness in soil treatment is not good. After applying sulfonylurea herbicides, the growth of sensitive weeds is quickly inhibited. After 3-5 days, the leaves lose their green color and the growth points die. However, complete weed death is slow and takes one to three weeks. Most sulfonylurea herbicides have strong selectivity and are safe for seasonal crops.