Title: Silage and whole-farm nutrient management Author
Submitted to: International Silage Conference
Publication Type: Proceedings
Publication Acceptance Date: June 4, 2009
Publication Date: July 27, 2009
Citation: Rotz, C.A. 2009. Silage and whole-farm nutrient management. In: Proceedings International Silage Conference, July 27-29, 2009, Madison, WI. 2009 CDROM. Interpretive Summary: An interpretive summary is not required.
Technical Abstract: The management of forage-based livestock farms is complex. A selected silage system can affect nutrient management by influencing the type, amount, and nutrient content of feeds fed. Manure handling procedures used on a farm can also affect the yield and nutrient contents of the forages produced. Software tools can aid farm planning by helping integrate the large amount of information that must be considered. The Integrated Farm System Model (IFSM) is a farm simulation software tool developed to evaluate the long-term effects of management changes on the performance, profitability, and environmental impact of forage-based production systems. Simulation of dairy production systems in the northeastern U.S. was used to illustrate the whole farm impacts of various silage production options and the effects of manure management decisions. Production and use of more corn silage, particularly when double cropped with rye silage, was found to reduce the loss and soil accumulation of nutrients with relatively small effects on farm profit. Use of a three cutting strategy for alfalfa production with longer regrowth periods between harvests reduced farm net return by $73 per cow with a small decrease in nutrient losses. Feeding lactating cows high forage diets with greater use of corn silage provided small environmental improvements with no effect on farm profit. Mechanical processing of corn silage had little impact on nutrient flows, but more efficient use of feed increased profitability by $57 per cow. An under application of manure N to corn land actually provided some environmental benefit, but at an economic loss to the producer. Use of subsurface application of manure reduced volatile N loss, but increased N leaching loss with little net cost to the producer. The evaluation and comparison of alternative production practices can help producers develop more environmentally friendly and profitable production systems.