玉米追肥要“四看”１．看土追肥土壤种类多，性质也不一样，所以，追尼要看土壤的性质而定。低洼地和碱地，要选用硝铵、硫酸铵、过磷酸钙等酸性或生理酸性肥料作追肥；酸性土壤应选用尿素、碳酸氢铵等碱性肥料作追肥；对保水、保肥能力差的砂土或砂壤土，应选用不易挥发... Corn dressing to “look” 1. See soil topsoil soil variety, the nature is not the same, therefore, chatini depends on the nature of the soil may be. Low-lying and alkaline, to use ammonium nitrate, ammonium sulfate, superphosphate and other acidic or physiological acid fertilizer for top-dressing; acidic soil should be used urea, ammonium bicarbonate and other alkaline fertilizer for top-dressing; water retention, fertilizer poor ability Sand or sandy loam, should be used less volatile ...