Summary and Implications
An ongoing two-year trial is being conducted to evaluate the effects of three different methods of initiating forage stockpiling on the quality and mass of forage available over the winter months (October through January). Methods of initiating stockpiling were spring strip-grazing, summer strip-grazing, and summer hay harvest. Forage mass, nutritional, and weather data were input into a ration balancing program with supplemental feed provided to maintain a body condition score (BCS) of five throughout the winter for fall-calving beef cows. Partial budget models were used to evaluate costs associated with the different treatment methods and compared to a standard winter hay feeding regime in a drylot scenario.
Spring strip-grazing generated the greatest stockpiled forage mass compared to all other treatments, but also had the lowest dry matter digestibility across sampling dates. There were no differences in crude protein (CP) content among different methods of initiation. The carrying capacity of drylot models was greatest but did not differ between stockpiling models. There was a tendency for drylot models to incur greater total costs ($/ac) than stockpile models. There were no statistical differences in total cost ($/ac) between models using stockpiled forage grazing by different methods of initiation and no statistical differences in gross ($/hd/d) or net ($/hd/d) costs across treatments. While spring strip-grazing resulted in greater forage mass, the quality of this forage was lower than summer treatments. With similar costs, the lower yields from summer stockpiling models (strip-grazing or hay harvest) could be compensated for by the higher nutritional quality of the forage.
Iowa State University
Stokes, Benjamin T.; Russell, James R.; Gunn, Patrick; and Schulz, Lee L.
"Progress Report: Effect of Stockpiling Initiation Method on Winter Forage Yield and Quality of Midwestern Cool-season Grass Pastures for Fall-calving Beef Cows,"
Animal Industry Report:
AS 663, ASL R3142.
Available at: https://lib.dr.iastate.edu/ans_air/vol663/iss1/15