"Three-high" corn refers to high-yielding corn varieties + high-density planting + high-level field management. The key points of the specific cultivation are: 1. Selection of land: Choose one or two terraced lands with convenient water sources or flat land, deep soil layer, loose texture, strong water retention and fertility, and reorganization. Planted on steep slopes. 2. Seedling raising methods: all use fertilizer group seedlings, fat groups sowing, cover film, seedling tube with the conventional cultivation, arch membrane must be tight around. 3. Reapply base fertilizer: apply the base fertilizer by means of trenching and fertilization, grab fine-grained sunny soil preparation, and proceed arbitrarily in the middle of the “3255â€, “Shuangsan†and other small belts as the standard reformed land. Infuse deep groove fertilizer, "double six feet" set aside to open double ditch. Every row of ditch is long and applies 0.5-0.6 kg of carbon fertilizer, 15-20 kg of heap slag, 0.6 kg of phosphate fertilizer, 0.2-0.3 kg of potassium chloride, 0.05 kg of zinc fertilizer, and one burden of water and feces. Earthworks. 4. Cover film: 2 days before planting, apply sufficient fertilizer and water, keep the soil moist, and cover the film tightly. Use a thin layer of soil to flatten it around and require tight, flat, airtight. 5. Transplanting method: when the corn seedlings have 2 leaves and 1 core, they are punched with a hole punch, spacing is 1.1--1.2 feet, the spacing is 4.5--5.5 inches, and each nest is planted with one plant, the first leaf Head toward the line. Pour enough root water, plant more than 4,000 mu, and cover it with fine dirt after planting. Early corn may not cover the mulch, but the arch must be covered after transplanting. When the tip of corn touches the membrane, the arch is removed. 6. Field management: Do not use MDF and jointing fertilizer in general. For plots with slow returning seedlings and poor seedlings, fertilizers can be applied to deep-fertilizers to apply fertilizer, 10 kg of urea for mu and 1--2 kg of zinc fertilizer. When attacking the big bell, the mu should use ammonium bicarbonate 50--60 kilograms against the manure water 40-ton in the narrow row of corn to dig pits in the middle of each pit, reclaim land and cover the nest, and remove the micro-membrane at the same time. "Three-high" corn in the whole field 3% - 5% draw male flowers, the use of Vitaling seedlings high, after the cut silk Xiong male, pest prevention and control, recycling of waste film to prevent pollution.