As the price of fertilizer nutrients rises, livestock manure becomes more valuable, and managers can take steps to capture as much of that value as possible. Iowa State University nutrient management specialist Joe Lally says feed-lot managers are moving away from once-a-year manure application on the closest field to one of multiple strategies, all of which are designed to improve the timing, rate, value and stewardship of this natural resource.
A variety of factors can influence the nutrient content of cattle manure, Lolly says. These include moisture content, distance to application fields, rations fed, bedding used and pen space per head. More space equals more surface area for manure nitrogen to volatilize. Cropping systems and existing soil nutrients also affect the value of a manure application to a field. One way feedlot managers can directly influence the nutrient value of manure is to scrape pens more often. Lally says that by scraping pens monthly, rather than just at pen closeout, feedlots can increase nitrogen recovery by 7 pounds per head. At today’s nitrogen values, the difference is a potential improvement of $3.85 per head from regular scraping. The