Animal Manure Management

Manure has value. That value may result from improvements in soil quality, increases in yield, and replacement of commercial nutrient required for crop production. This article will focus on the economic benefits of manure.

The workshops and online course are designed to help farmers increase the economic value of manure and to understand and implement the nutrient management planning requirements of Nebraska’s Department of Environmental Quality regulations. Topics covered include: updates on manure management regulations, value of manure as a fertilizer and soil amendment, biosecurity on livestock operations, and more. Anyone currently using manure or considering adding manure to their cropping system fertility program is encouraged to participate.

Land application of organic materials for soil management in Nebraska is important. The availability of applied organic N and the fertilizer N substitution values of applied organic materials is not well predicted. The uncertainty of applied organic N availability leads to over-application of fertilizer N resulting in low efficiency of applied N use. Research has been done to validate or adapt canopy sensor guided in-season N application practices for fields with manure or other organic material applied, and to improve the prediction of the fertilizer N substitution values for organic materials.

Soil health management refers to the preservation and improvement in soil physical, chemical, and biological properties to maximize the productive capacity of soil. Cover crops and reduced tillage are promoted for improving soil health; however, soil amendments such as application of livestock manure and municipal biosolids have received less attention as a soil health improvement practice. A literature review, funded by the North Central Region Water Network and the Soil Health Institute, was conducted to summarize and discuss results of studies reporting chemical, physical, and biological soil properties from application of livestock manure, animal by-products (i.e. compost), and municipal biosolids and to identify further research needs.

A resource reality of cattle production is that only 10-30% of the nitrogen (N) that is consumed (i.e. fed protein) is utilized by animals for growth, reproduction, milk production, and maintenance needs. Unused N is excreted, primarily in urine. While livestock production is not the only source of N, producers should recognize that agriculture is clearly the dominant contributor of N to the environment on regional and national scales, and animal manure is a key source along with commercial fertilizer. In April of 2017, the DC Circuit Court of Appeals ruled that EPA would have to require animal feeding operations to report ammonia emissions. EPA expects to receive a court mandate on January 22, 2018, enforcing its ruling and opening livestock and poultry operations to consideration under CERCLA/EPCRA.

Winter cereal rye planted as a cover crop has been shown effective in capturing nitrate before it leaches from the root zone. We conducted on-farm trials in central and southern Minnesota to determine if a rye cover crop would capture significant root-zone nitrate in the fall and spring but release it in time to maintain yield in the subsequent corn crop.

Manure is often viewed by many as an environmental liability. However, if manure is applied at rates equal to or less than the nitrogen (N) requirement of a crop, can manure produce environmental benefits over commercial fertilizer? This was the focus of an Asian research group which summarized the results of 141 published studies from Asia, Europe, and the U.S. comparing manure substitution for fertilizer. This article summarizes the “Take Home Messages” from this research paper.

Abandoned manure storages present a risk to the environment by accidental overflow or leakage due to lack of management. It is in the best interest of the environment and the property owner, who is liable for any environmental damage resulting from any discharge, whether leakage or overflow, to properly close any unused manure storage structure.

When designed properly, runoff holding ponds, lagoons, and other earthen manure storage structures are sized to contain manure, process wastewater, and storm water that drain into or fall on them throughout their designed storage period. Excess precipitation, particularly chronic wet weather, can lead to concerns about storages overflowing even when they have been managed correctly.

Because of a growing concern about manure irrigation, the University of Wisconsin Extension assembled a workgroup to research the concerns. The workgroup included scientists, public health specialists, state agency experts, farmers, conservationists and others. Over the course of two years, the group gathered and studied the science of manure irrigation, which culminated in a report that contains findings, responses and recommendations. This article will review a few of their findings related to bacterial transport as well as highlight some of the reasons why a farmer might opt to apply manure via irrigation rather than other ways.

Management is the key to keeping dust under control. By using some basic dust control techniques, open feedlots can prevent or minimize the problem.

A Nebraska Extension pilot project is assisting pork producers in calculating their swine farm environmental sustainability footprints in a joint effort with the University of Minnesota Extension.