How much manure can or should be applied?
To answer this question several factors must be considered and often many assumptions have to be made. Manure application rates can be calculated based on the soil nitrogen limits of AOPA, the nitrogen requirements of intended crops, or the phosphorus requirement of one or more years of crop production. Each of these calculations will give a different answer about how much manure can be applied (with the AOPA basis allowing for the greatest amount of manure in most situations and the phosphorus basis being the most restrictive). Assumptions must be made about the proportion of the nitrogen or phosphorus that is in the mineral form, the nutrients that are mineralized each year, and the nutrient loss after application that never becomes part of the soil-plant system. Putting Theory Into Practice: A Nutrient Management Planning Case Study provides practical examples of calculating manure application rates. The Alberta Manure Management Planner is another useful tool for planning manure ap
