Choosing the rate and amount of nitrogen to apply should be derived from your soil and yield analyses.
However, choosing the right nitrogen application form and method should be determined by soil, environmental, weather and crop conditions. This is because soil, environmental, weather and crop conditions are the primary components that we have to manage the key nitrogen loss areas of denitrification, leaching and surface volatilization.
Denitrification occurs when nitrogen is present in the soil but there is not enough oxygen present to supply the needs of bacteria and microorganisms in the soil. Three conditions that promote denitrification are wet soils, compaction and warm temperatures.
Leaching occurs when the soil has more incoming water than it has the capacity to hold, causing nitrate to move along with the water across topsoil and through the soil profile.
Surface volatilization occurs when urea forms of nitrogen break down into ammonia gas. This happens when urea forms of nitrogen are applied to a field but not in direct contact with the soil.