Livestock production under fire and grazing management

Fire and grazing were historically used on the Great Plains by Native Americans to attract bison. Fire and grazing can be used together on rangelands to increase biodiversity and improve wildlife habitat. From a conservation perspective, there is a general belief that stocking rates must be lower than traditional grazing methods which may compromise livestock production. Conservation practices are important on today's rangelands; therefore, studying animal performance within a conservation-based strategy is essential.

In recent research, scientists evaluated cattle performance associated with a management strategy identified as pyric-herbivory, or fire and grazing. Two different sites in Oklahoma were used; one tallgrass prairie (eight years) and one mixed-grass prairie (11 years). Stocking rates were based on USDA-NRCS recommended rates for each site. For the tallgrass prairie site, traditionally managed pastures were burned entirely every three years. Conservation managed pastures were burned in patches seasonally, completing a burn rotation every three years. For the mixed-grass prairie, traditionally managed pastures were not burned and conservation managed pastures were spring burned every four years. Seasonal grazing by stocker cattle was done for the first four years of the study. Individual weights were taken at the beginning and end of each grazing season to evaluate performance. At the end of year four, stocker cattle were replaced by cow-calf pairs grazing year-long on the tallgrass prairie site. Cow body condition score was determined for each cow monthly, and calves were weighed at birth and weaning to determine calf weight gain.

For the first four years, animal performance did not differ between traditional management and conservation-based management for either site. For the remaining four years at the tallgrass site, calf weaning weights and cow BCS were similar. However, on the conservation-based managed tallgrass prairie, calf weaning weights were more uniform. For the remainder of the 11 years at the mixed-grass site, stocker cattle gained 48 lbs. more per animal with conservation-based grazing management.

On the tallgrass prairie, traditional and conservation-based management were not different; there was no loss in production using conservation-based management. On the mixed-grass prairie, conservation-based management cattle gained more weight than cattle managed traditionally during the final seven years. This difference was attributed to periodic burning.  Cattle on pastures that were patch-burned had access to recently burned areas which provided higher quality forage. Conservation-based management may not cause a loss in cattle production, and in some cases may result in increased weight gains and less variation in production.

Source: Wesley Hartmann