Insects (generally corn borer larvae) in the core of corn seedlings can be mixed with 5 times of fine sand by 1% phoxim granules or 3% Guangmiedan granules (per mu1-2kg), and then the soil is scattered in the corner of corn, so that the control effect can be achieved. You can also mix 2.5% Rise of the Legend Ling 1 granule (250g) into 3-4kg of fine sand, and sprinkle 1 g of fine sand (heart-forming leaves) on each corn seedling after mixing well.