After corn has been sprayed with herbicide and then watered, is the herbicide still effective? Scientifically speaking, this depends on the interval between the two; the longer the interval, the better the herbicide can take effect. It is best to extend the interval to more than two days, otherwise the herbicide may fail to work because it is not absorbed thoroughly enough by the weeds.

Apart from that, there is another major problem: if the interval between applying the herbicide and watering is too short, the herbicide may dissolve in the water and enter the soil, damaging the corn roots and causing herbicide injury.

As for the pre-emergence herbicides currently used in production, applied after corn sowing but before the weeds emerge, watering afterwards can also wash the herbicide down into the ground and harm the roots.

Therefore, when using herbicides in production, you must leave a sufficient interval before watering. However, Science Agriculture still wants to point out a few issues regarding herbicide use: 1. Pay attention to cleaning before and after herbicide use. 2. Always use two-stage dilution when applying herbicides. 3. Follow the herbicide label and apply according to the instructions. 4. It is best to fit a shield in front of the nozzle so the spray is directed. 5. Choose windless weather for spraying.?

One last point: before you have confirmed whether the herbicide is effective, do not rush to spray the herbicide again. Avoid repeated application due to slow efficacy, which can cause herbicide injury.

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