Fall 2003
Manure Management: Successes and Challenges
by Mahdi Al-Kaisi and Mark Licht, Department of Agronomy, and Mark Hanna, Department of Agricultural and Biosystems Engineering
As part of an integrated tillage and manure management demonstration project in NE Iowa, a survey evaluated the impact of improved management practices in tillage and manure management. The survey was conducted with participants in the project. Cooperators consider manure a valuable nutrient source for crop production; 57 percent of them believe that using manure alone can produce corn yields comparable to commercial nitrogen (N). All cooperators take manure samples for analysis every year, to determine manure application rates. This information is important because 71 percent of the cooperators self-apply manure: 86 percent of them applied manure based on N needs while only 14 percent based on phosphorus (P) needs.
Hubs and Spokes cooperators
prepare to calibrate
manure application equipment.
From data obtained from on-farm trials, cooperators are finding that optimal yields can be achieved with manure use only and result in a reduction of commercial N-fertilizer use. Thirty percent of the cooperators have stopped applying commercial N-fertilizer on other (non-trial) manured fields and 14 percent have reduced supplemental commercial N by 50 lbs/acre. Cooperators are also realizing the consequences manure can have on the environment. The prevailing attitude among them was, “if you over-apply N and you do not see any yield response, this means the N is going somewhere.” Another attitude change was related to their understanding of manure as a nutrient source rather than a waste product. These changes in cooperator behavior and attitudes towards manure use and management are a very significant step in achieving integrated tillage and manure management.
When producers were asked about the importance of manure management, the consensus was “it helps us fine-tune our management practices” and “the project gives an opportunity to increase manure management knowledge.” Cooperators appreciate timely, site-specific information that enables them to fine-tune their individual practices. They also stress that on-farm application equipment. manure management trials are “actual results” and “it’s exactly what happens at our fields.” Cooperators also mentioned “the information is site specific and readily available to us.” Many of them indicated that it is an advantage to have replicated and repeatable data for making manure management decisions in on-farm trials.
Cooperators are enthusiastic about participating in on-farm manure management demonstrations. Seventy-one percent of them believe they learned or improved skills by working with the project and 79 percent indicated they are managing manure much more efficiently now.
However, cooperators have expressed concerns about tillage and manure management. Currently, they foresee the following challenges related to tillage and manure management: incorporating residue cover vs. manure, achieving accurate application rates with available technology, timing manure application and sample analysis, deciding on N vs. P based application rates, having cost-share funds available for manure application technology (i.e. flow controllers), dealing with the costs associated with hauling, applicators, technology, and sample analyses.
For more information regarding this demonstration project, please see the project summary reports for the Hubs and Spokes Demonstration project at this Web site.
The Hubs and Spokes Project, part of the Integrated Farm/Livestock Management (IFLM) Demonstration Project, receives funding from the Iowa Department of Agriculture and Land Stewardship, Division of Soil Conservation.
