Do you know all these key points of weeding in the corn field? How to choose herbicides?

In recent years, the use of herbicides in corn fields has become more and more common. however, many farmers have found that herbicides purchased at the same time are effective in one field and ineffective in the other. What is the reason for this? In fact, the reason for this phenomenon is not only the difference in the quality of herbicide products, but also affected by many other external factors. Next, let's talk about the main points of weeding in corn fields.

1. Select herbicides suitable for corn application.

Each herbicide requires different crops and strong selectivity. except for special herbicides in corn field, other herbicides can not be used indiscriminately in corn field. In general, herbicides used for the first time should be cautious, otherwise, it may cause serious consequences.

2. Master the appropriate application period

The weed control effect of herbicides is related to the period of use, which should be used in the period of the best effect of killing weeds and the safest for corn. For example, the main action site of Acetochlor herbicide on weeds is coleoptile and young roots. therefore, the effect of this herbicide is ideal before weed emergence, but has no obvious killing effect on weeds.

3. Before using medicine, we should know the planting situation of the surrounding crops.

Some herbicides can kill weeds and are harmless to corn, so they can be safely used in corn fields, but they are very harmful to some crops and vegetables. For example, 2B4 drop of butyl ester can be applied to corn, sorghum and millet at 4-5 leaf stage after emergence. However, cotton and soybeans are sensitive to the herbicide, and should be used cautiously when planting cotton in neighboring areas, especially when the terrain is lower than that of corn or in the lower tuyere, so as not to harm the neighboring areas.

4. Effect on the following crops.

Some herbicides have a long residual period, and improper application may cause harm to sensitive succeeding crops. For example, atrazine is an excellent herbicide in corn field, but it has a long residual period and is sensitive to legume crops, so the use time should take into account the arrangement and planting time of the next crop.

5. Look at the sky, the earth and the crops

Do not apply it before the heavy rain, so as to avoid the loss or accumulation of herbicides caused by Rain Water erosion, resulting in reduced efficacy or drug damage. The effect can also be reduced when the soil is too dry. In the seedling stage, the weeds are small, so we should choose the internal absorption of herbicides. After the big trumpet period of corn, when the weeds are large, it is better to choose germicidal herbicides.

6. Strictly control the concentration and method of use.

Because there are many kinds of herbicides that can be used in corn fields, and the required concentrations of different herbicides are different. Therefore, it is necessary to master the concentration and dosage before use. If the concentration is too low and the dosage is too little, it may not play the role of weeding, while if the concentration is too high and the dosage is too large, it will often have a harmful effect on corn. Generally speaking, commercial drugs will give a certain concentration and dosage range. In the plots with high soil organic matter content and low soil water content, the upper limit of safety concentration should be used, on the contrary, the lower limit should be used. The use of herbicides should pay special attention to spray evenly, do not miss spray; do not spray on corn after seedling, so as to avoid harm to corn.