Manure

Earlier this year, I spent several hours with Rejean Houle, president of US Farm Systems, in Tulare, California. In addition to telling me about his system for separating manure solids for creating bedding, he answered a few questions I posed to him regarding manure management, bedding and nutrient disposal. Portions of my conversation with Rejean follow.

Manure is an inevitable byproduct of the production of meat and milk destined for human consumption. Excessive excretion of manure and manure nutrients represents inefficiencies that increase feed costs, increase the environmental impact of dairy farming and increase costs associated with moving and storing manure. Profitability often can be enhanced when feeding and management practices are used that reduce manure production per unit of milk produced. Furthermore, good environmental stewardship will maintain the generally positive public image of dairy farming.

Water quality in the U.S. is threatened by contamination with nutrients, primarily nitrogen (N) and phosphorus (P). Animal manure can be a valuable resource for farmers, providing nutrients, improving soil structure and increasing vegetative cover to reduce erosion potential. At the same time, application of manure nutrients in excess of crop requirements can result in environmental contamination.

Environmental concerns with P are primarily associated with pollution of surface water (streams, lakes, rivers). Excess P in water causes algae to grow rapidly, or to “bloom.” The decomposition of this algae consumes dissolved oxygen in the water and impairs the survival and productivity of fish, clams, crabs, oysters and other animal life. An algae bloom and subsequent decrease in dissolved oxygen may be caused by runoff of P when application to land is in excess of crop requirements.

A field-by-field nutrient management program requires multiple components to maintain adequate fertility for crop growth and development. A well-designed soil sampling plan, including proper soil test interpretations along with manure sampling, manure nutrient analysis, equipment calibration, appropriate application rates and application methods are all necessary components of a nutrient management plan. Implementing these components allows manure to be recognized and used as a credible nutrient resource, potentially reducing input costs and the potential of environmental impacts.

I recently interviewed Terry Feldmann, head of Maurer-Stutz’s agricultural engineering division, about the manure management landscape that dairy producers face today. Feldmann assists livestock producers planning, designing, siting and building new or expanded facilities in Illinois and surrounding states.

Leon Weaver hopes new changes to his manure management system cut in half the time and management it currently takes to manage his dairy’s 40 million gallons of manure. Weaver, an owner of Bridgewater Dairy in Montpelier, Ohio, jokingly admits that if his new McLanahan sand separator system works using manure press effluent as wash water, he’ll use the extra time and money he’d otherwise spend managing manure to go fishing.