Manure Storage and Land Application - Where are we going? How fast can we get there?

Mr. Jon Rausch, Waste Management Extension Associate, The Ohio State University 

In today's economic climate, manure nutrients have more value than ever. The cost of commercial nitrogen (N) is at an all time high and continuing to increase. Phosphorous (P) and potassium (K) are following this same trend. The demand for animal manure as a viable nutrient resource is once again being determined by economic forces. What has changed is the addition of environmental protection through regulations and the voice of society.

Historically, animal manure has been spread very close to the animal production facility, resulting in soil nutrient levels in excess of plant requirements. As farm size, environmental concerns, and crop nutrient input cost increase, the need to move nutrients further has become more necessary and more economical.

Water and air quality standards should drive the environmental requirements placed upon manure handling, storage, and nutrient recycling practices. Water quality impacts from land use activities are becoming more evident as restrictions to point source discharges become more stringent. This translates into increased scrutiny of non-point sources in an attempt to advance water quality improvements. These non-point sources primarily stem from land use activities, and the largest land owners have traditionally been rooted in agriculture.

Air quality standards are looming on the horizon as research efforts begin and air quality issues play out in the scientific, policy, and public opinion arena. Gas, odor, and particulate emissions associated with the animal production facilities are the primary concerns relative to air quality. Air quality recommendations and regulations will most likely develop in much the same manner as today's water quality standards, but probably at a faster pace.

Social acceptability of animal manure handling, storage, and nutrient recycling may be the largest unknown for many producers, especially as farm size increases. Finding a system that strikes a balance between the economic requirement for the farm and the need to mitigate environmental and social concerns will continue to be a significant challenge. Certainly, the costs of manure management will increase. These additional costs will have to be off-set by some source of revenue (cost reduction).

One source is fully recycling manure nutrients on and off the farm. Efficient utilization of these nutrients can be used to reduce the out-of-pocket cost of purchasing commercial fertilizer or become a revenue source from the sale of these nutrients. Many animal operations have the potential to broker/sell manure nutrients and associated agronomic benefits. However, this typically requires more time and resources dedicated to the management of manure.

Manure requires management to minimize adverse impacts to farm profitability, the environment, and neighbors. As crop production costs and the pressure from outside sources continue to increase, those individuals that find less costly alternatives will be more profitable. Animal manure may be one of these alternatives and as the demand for this commodity increases, the need to increase management will also increase. For example, to reap maximum return from manure may require minimizing the water content to concentrate the nutrients. Again, this may require more financial and human capital to provide a product that would demand such a premium.

Manure management is different on every farm. For some, the sale of manure nutrients and "mining" excess nutrients currently available may be more economical than transporting manure further from the production site. For others, investing capital in nutrient segregation technologies, such as liquid-solid separation, may be more economic. Yet, others may find the addition of adsorbing organic sources will transform a relatively sloppy manure mix into a stackable and marketable commodity with the addition of financial and human capital. The speed at which producers move toward changing manure handling, storage, and application practices will be driven by economic, environmental, and social demands.