Nitrate nitrogen is the dominant form of plant-available nitrogen in soils, since even ammonium nitrogen is rapidly converted to nitrate nitrogen under Kentucky field conditions. Nitrogen in the nitrate form can be lost by leaching in the drainage water and by denitrification when the soil is saturated with water for a relatively short period of time. With the increased cost and short supply of nitrogen fertilizers, it is especially important that applications be made at a time and in a way that will minimize losses.
Peaslee, Doyle; Bitzer, Morris J.; and Miller, Harold F., "Effect of Topdressing Different Forms of Nitrogen Fertilizer on Corn" (1975). Agronomy Notes. 122.