What precautions should be taken when spraying herbicides in winter?
What are the characteristics of using herbicides in winter? How can herbicides be applied in winter for good results? Experienced readers are also asked to help answer. Generally, when herbicides are applied during low-temperature periods, the efficacy is released slowly, the ability of weeds to absorb the chemicals decreases, and control effectiveness is reduced. Therefore, when applying herbicides in winter, the following key points should be mastered....
What are the characteristics of using herbicides in winter? How can herbicides be applied in winter for good results? Experienced readers are also asked to help answer.Generally, when herbicides are applied during low-temperature periods, the efficacy is released slowly, the ability of weeds to absorb the chemicals decreases, and control effectiveness is reduced. Therefore, when applying herbicides in winter, the following key points should be mastered.
1. Apply according to the weather: after temperatures drop in autumn and winter, strong winds are often present, which is not conducive to the effectiveness of herbicides. Application should be timed for sunny periods when the temperature is relatively high. At this time, the physiological metabolism of weeds is more active, which helps the chemicals conduct within the plant and gives good weed control. If application is delayed until the overwintering period, it is very difficult to kill weeds. In particular, herbicides containing isoproturon may cause freezing injury to wheat seedlings when used at low temperatures.
2. Apply thoroughly and evenly: strictly control the spraying concentration to improve weed control effectiveness. Do not arbitrarily reduce the amount of water used, so as to ensure thorough and even application and prevent phytotoxicity.
3. Add nitrogen fertilizer to improve control effectiveness: when applying chemicals such as MCPA, mixing in an appropriate amount of nitrogen fertilizer such as urea can significantly improve control effectiveness. The mechanism is that fertilizers such as urea can reduce the surface tension and pH of the herbicide solution and enhance adhesion.