By Everett Brazil, III
Auburn University researchers are finding that by controlling the loader belt and spinner speed on litter spreaders they can reduce overlap applications by more than 10 percent. In fact, their four years of study shows a 17% improvement in uniformity with specially-equipped spreaders.
Wes Wood, agronomy and soils professor at Auburn, says the variability of litter size and weight makes it difficult to spread the material uniformly with a manually-set spinner disc and unloader belt. To offset those shortcoming, he and fellow researcher John Fulton, an Auburn ag engineer, mounted hydraulic controls and proportioning valves in the cab of the tractor to allow on-the-go adjustments for litter size, mass and field conditions. The results are significant, and for the first time, allow litter to be applied at variable rates via GPS technology.
The precise control of poultry litter application makes sense from an economic standpoint, since litter is valuable fertilizer and many times comes with hefty transportation costs. In addition, the precise control of how much litter is used is a tool to prevent nitrogen and phosphorus leaching into surface and groundwater, the researchers agree.