Does Manure Treatment Affect Soil Nitrogen Availability?

Does Manure Treatment Affect Soil Nitrogen Availability?

Summary

Manure samples and manure treatment system data were collected from cooperating producers in July and August 2007. Soil samples for the incubation study were also collected and processed. Initial total carbon (C) and nitrogen (N) analyses were conducted to determine appropriate application rates for the incubation study. Preliminary analyses of manure total C and N data indicate considerable variation among farms and treatment systems within farms, as expected. Additional manure analyses are ongoing. Method development for rapid determination of ammonium-N and nitrate-N in incubated soils is ongoing. Soil incubations will begin in March, 2008 and continue through June, 2008. Outreach has included discussion of the project at area Soil, Water, and Nutrient Management Meetings and to regional producer groups.

Objectives/Performance Targets

1. Collect manure samples representative of treatment systems on WI dairy farms
2. Collect information regarding treatment systems used at cooperating farms.
3. Collect soil samples representative of Wisconsin soil groups
4. Initiate manure analyses.
5. Determine methods for set-up, sample collection, and analyses of soil incubation samples.

Accomplishments/Milestones

All objectives/performance targets for year one were achieved.

Impacts and Contributions/Outcomes

Preliminary data from initial manure total C and N analyses were presented during the 2007 Area Soil, Water, and Nutrient Management Meetings held at various locations throughout the WI in November and December, 2007. The presentation was titled “Nitrogen Availability From Manipulated Manures” Total attendance at all meetings was 463, and included producers, agronomy professionals, and state and federal agency personnel. Results from survey data indicate overall positive response from Area Meeting attendees, and indicate interest in seeing the results of the incubation study. Additionally, a similar presentation was given to a group of approximately 60 dairy producers in February 2008.