John Lory is in the business of moving and managing nutrients. Lory, an extension associate professor in the Division of Plant Sciences at MU, is exploring three winter feeding strategies to evaluate the best way to use manure from cattle to fertilize the pasture for the following season.
Lory said winter feeding practices vary, but traditionally, producers feed hay in one spot in a pasture over the winter. With increases in fertilizer prices, producers are recognizing the value of the fertilizer their cows provide and looking for ways to maximize its effectiveness while maintaining cattle performance and judicious use of hay—a commodity that is significantly more expensive during a drought year like 2012.
“We have an interest in managing animals to improve manure distribution and to use their manure as a fertilizer; it’s difficult to track manure distribution in a field, so this study is working with tools such as aerial photos, soil samples and sonic sensor readings of yield response in a small scale to try to track the impact of manure,” Lory said. “We ultimately want to develop strategies where we can make manure a more reliable fertilizer; in order to do that, you need to have these tools to gain that information.”
The study is ongoing at the Forage Systems Research Center near Linneus, Mo., and uses three approaches to feeding hay to cattle.
Cows are fitted with radio collars so researchers can track their location in the pasture. They spend most of their time near their food source. “Clearly by moving hay around, we can see where the cows go, and thus where their manure and the nutrients in it are distributed,” Lory said.
Soil samples provide information on phosphorus and potassium distribution and the forage yield and aerial photos provide data on the nitrogen response to the three approaches.
“It takes additional time and effort to move hay around the pasture and when you move the rings around there’s some damage that happens to that paddock—how much does that offset the benefit—that’s what we’re trying to answer,” Lory said. “We’re quantifying the benefits to see how much they offset the costs. If you can get the same feed efficiency with unrolled hay but you don’t chew up the paddocks, that’s really good for the producer’s bottom line and the health of the pastures.”
In addition to comparing the strategies’ effects on nutrients in the pasture and cow performance, Lory is also examining how technologies such as sonic sensors can provide detailed information on forage height. The sensors are mounted to all-terrain vehicles (ATVs) where they collect readings that can be easily uploaded to a computer.
At the conclusion of the study they’ll provide an economic analysis, animal performance data, and report savings on nitrogen, potassium and phosphorus inputs and share recommendations for using new technologies to inform management decisions.