Tips for the fall manure application season
It's that time of year again – the end of another year spent planting, cultivating, sweating, pacing, worrying, and doing all the things farmers do throughout the year just to get to harvest. As the crops come off the field, livestock manure often goes onto the field. Here are some tips for the fall manure application season:
- Avoid entering manure storage areas – The breakdown of organic matter in manure results in the release of many gases, including hydrogen sulfide, ammonia, methane, and carbon dioxide. Exposure to these gases, especially hydrogen sulfide, can be toxic to humans causing loss of consciousness and even death. Whenever possible do not enter a manure storage area. If it is absolutely necessary to enter the confined space, provide additional forced ventilation into the area by turning on all fans. The person entering the confined area must wear a supplied-air respirator and be properly trained in the use of this equipment. A worker in a confined space or manure storage area should wear a body harness with a safety line. The safety line should be held by enough people so that the worker can be pulled out of the area if a problem develops. Provide a clear escape path for the worker to exit the manure storage area quickly.
- Provide adequate ventilation – Liquid manure storage systems need to be agitated to mix the solids that have settled to the bottom of the pit. During this agitation process, high levels of dangerous gases can be released, which can cause sickness or death to people and animals. It is best if the barn is empty during pit agitation. If animals or humans are present during mixing, be sure to provide maximum ventilation to the area.
- Follow all highway rules – Before heading out onto the road, make sure all safety equipment such as reflector lights, hazard lights, and slow moving vehicles signs are in place and working properly on the manure application equipment. Keep safety equipment clean and replace if it is faded. Reduce speed for hills, rough ground, curves and turns, and before approaching intersections or stops.
- Test soil and manure before application – The best way to make sure you are applying manure at the appropriate rate is to test the soil on the field where manure will be applied and test the manure to be applied to the field. Nutrient content in soil and manure can vary greatly, so be sure to take representative samples for soil and manure analysis. Many times manure samples are collected during the fall application process and test results are not available before manure is applied to land. In this case, be sure to keep accurate records of manure tests from year to year remembering that diet, weather, bedding materials, and many other variables can cause year to year variation in manure characteristics. If you do not have past manure test results or are not confident in the results, book values can be used to provide estimates of the nutrient value of the manure.
- Calibrate manure application equipment – Correctly calibrated manure equipment will help ensure appropriate manure application rates. It will also save money and reduce nitrogen loss to the environment.
- Follow all manure application guidelines – All livestock operations in Minnesota are required to manage the manure from their operation to prevent pollution of waters, to follow the maximum nutrient rate limits, and maintain setbacks from sensitive features such as open tile inlets, intermittent streams, lakes, streams, mines and quarries, and sinkholes. Maximum manure application rates are limited by crop-available nitrogen on the land. All sources of nitrogen must be considered including commercial fertilizer, manure applied during the previous cropping year, soil organic matter, irrigation water, and legumes grown during the previous year. Phosphorus-based rate requirements may apply in sensitive areas or on land with phosphorus levels exceeding 75 ppm Bray P1 or 60 ppm Olsen. Livestock operations with 300 or more animal units are also required to test manure for nitrogen and phosphorus content, test soils for phosphorus, develop a manure management plan, and keep land application records.
- Have an emergency action plan for manure spills – This is a detailed plan on what to do if you have an accident or emergency such as a manure spill. An effective emergency action plan can reduce the severity of emergencies, the risk to humans and animals, the economic loss, and potential environmental pollution. State law requires that manure spills or leaks be reported immediately to the Minnesota Duty Officer at 1-800-422-0798. For more information about farm safety or writing an emergency action plan, visit the University of Minnesota Agriculture and Health Safety website. For more information on manure application, visit the Minnesota Pollution Control Agency website.
Published in Dairy Star October 14, 2006