Calculating the Value of Manure for Crop Production

Manure has value for crop production when it provides nutrients or soil amendments needed for optimum crop yields. Manure does not supply nutrients in balance with crop needs, but has the adavantage of slowly releasing nutrients which reduces the risk of nitrate leaching. Manure nutrient content varies widely due to weather conditions, the livestock facility, manure storage systems, the age of manure and feed composition. Low nutrient concentration due to weathering and dilution with water or soil decreases the value of manure. The organic material in manure also can improve soil productivity by increasing the water infiltration rate and water holding capacity. On some soils, this gain in productivity may be more than its nutrient value. A worksheet to calculate the value of manure is provided.