It is highly desirable to recycle nutrients and organic matter contained in these materials. However, some potential hazards may be encountered when organic materials are applied to the soil-plant system for crop production if good management practices are not followed. These can include excessive additions of nutrients, additions of trace elements and trace organic chemicals, pathogens, soil physical problems, odors and insects which spread disease. However, this agency has not required livestock producers to obtain permits for land application of manures, except where poor manure handling and management have contaminated water. For more information concerning MDNR requirements, contact the MDNR Waste Management Division, PO Box 30028, Lansing, MI 48909.
Animal manure can be a valuable source of nutrients for crop production.
However, the nutrient varies considerably from farm to farm, depending on many factors, including animal species, feed used, amount and type of bedding, and amount of water added. Due to this wide variation, average nutrient values can be very misleading. The recommended method to determine the nutrient content for manure is to sample the manure and send it to a laboratory for analysis. The manure analysis should then be used in conjunction with the rate of application to calculate the amount of nutrients supplied from the manure. By giving credit for nutrients supplied from manure, the risk of water pollution will be minimized and economic benefits will also be gained.