ent concentrations from different animals and even within animal species, can vary from sample to sample, be in liquid or dry forms, and can require large application volumes because of low nutrient concentrations. Additionally, nutrients such as N and P within manure can be tied up until microorganisms are able to free them from fibrous feed or bedding components; however, K is readily available for crop uptake.
Q. What are the commonly used methods of manure application?
Broadcast, injection, and irrigation are the principle methods for manure application. Benefits of broadcast applications include quick delivery and wider application widths compared to injection. Broadcasting may reach widths of 50 feet while injection systems are much narrower and would require more time to apply. However, without immediate incorporation, broadcast manure can be subject to loss of P through surface runoff, N volatilization, and result in complaints by neighbors from odor. If manure needs to be applied on snow covered fields, the fields should be reasonably flat, with slopes less than 5%, and away from streams and waterways.
Injection and irrigation of liquid manure forms can help control application variability, provide a better means of matching application to the crop's time of nutrient need, and help address some environmental issues. Injection allows for application to growing crops such as alfalfa, grass, or cover crops, and can be potentially used as a sidedress in corn. Injection systems are also compatible with no-till management. However, labor and equipment costs for injectable systems can be high. Regardless of the potential benefits of injection systems, many still prefer broadcasting manure because of the speed of application.
Q. What are the pros and cons of using center pivots for manure application?
Benefits of using center pivots to distribute liquid manure include the ability to apply during the growing season when the crop is in most need of nutrients, less risk of surface runoff, less potential for nutrient leaching because plants can start accessing the nutrients soon after application, lower distribution costs for producers and reduced risk of spills compared to manure haulers/tankers, reduced traffic and potential damage to roadways, and reduced soil compaction.
However, issues have been expressed regarding odor spikes, risk of influencing air quality with particulates, surface and groundwater effects, and reduction of aquifers. Therefore, these issues should be evaluated for the local area before irrigation equipment is purchased for the sole benefit of manure distribution.
Hoeft, R. et al. 2000. Modern corn and soybean production. First Edition. MCSP Publications, Champaign, IL.
Hoeft, R. and Peck, T. 2002. Chapter 11: Soil testing and fertility. Illinois Agronomy Handbook. University of Illinois.
Karlen, D.L. et al. 1988. Aerial accumulation and partitioning of nutrients by corn. Agronomy Journal 80:232-242.
Sawyer, J. 2003. Drought impacts on soil fertility. Integrated Crop Management. Iowa State University. https://lib.dr.iastate.edu/cgi/viewcontent.cgi?article=2642&context=cropnews
Understanding manure irrigation. Benefits and Concerns. University of Wisconsin. 2016. https://fyi.extension.wisc.edu/manureirrigation/benefits-concerns/
Land application of animal manure. 1996. Clemson University. https://www.clemson.edu/public/regulatory/ag-srvc-lab/animal-waste/manure.pdf
Atiyeh, D., Ketterings, Q., Czymmek, K., Godwin, G., Potter, S., Bossard, S., Maquire, R. (Virginia Tech), and Kleinman, P. (USDA-ARS). 2015. Liquid manure injection. Fact Sheet 87. Cornell University. http://nmsp.cals.cornell.edu/publications/factsheets/factsheet87.pdf
Sawyer, J.E. and Mallarino, A.P. 2016. Using manure nutrients for crop production. PMR 1003. Iowa State University. file:///C:/Users/evrqq/Downloads/PMR1003.pdf