By Dr. John D. Bailey, PhD
DCD’s benefit is limited by soil type and field capacity
Straight commodity products, like DCD, limit the scope of benefit to a very narrow set of field circumstances:
– On sandy soils with low CEC (or simply shallow soils) where water input exceeds the soil’s ability to hold water against drainage, especially on irrigated fields, the 34% DCD is the best choice for nitrogen protection.
– On loamy soils with high CEC (or simply deep soils) where water input rarely exceeds the soil’s ability to hold water against drainage, especially in dryland production, the 34% DCD product is NOT the best choice.
DCD’s benefit is limited by the type of fertilizer and the tillage system on the farm
Commodity products like DCD (I don’t care what the percentage is) will not protect urea and UAN from urease-mediated ammonia volatility loss. Therefore, if farmers are using urea or UAN fertilizers that stay on the surface for a while, using a straight DCD product is super risky to the farmer and is NOT the preferred choice.