|JOHNSON, BILLY R|
Submitted to: Journal of Sustainable Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/17/2007
Publication Date: 7/1/2008
Citation: Brink, G.E., Sistani, K.R., Oldham, J.L., Kingery, W.E., Johnson, B. 2008. Broiler litter application rate effects on bermudagrass nutrient uptake and phosphorus level of soils differing in application history. Journal of Sustainable Agriculture. 31:79-94.
Interpretive Summary: Broiler litter is a mixture of chicken manure, wasted feed, feathers, and wood shavings or other crop residue. It is applied at a range of rates to warm-season grasses in the southeastern United States, sometimes with insufficient knowledge of how rate impacts crop growth, nutrient uptake, and soil nutrient status. Our objective was to determine how litter application rate affected the growth and nutrient uptake of bermudagrass growing on a low and high fertility soil. We found that bermudagrass yielded more forage and removed more nutrients from the soil when litter was applied to a soil with low initial fertility. All application rates led to significant increases in soil nutrient levels. The results of this experiment emphasize the decreasing efficiency of nutrient utilization by bermudagrass as litter application rate and history of application increases.
Technical Abstract: The effect of broiler litter application rate on bermudagrass (Cynodon dactylon (L.) Pers.) yield and nutrient uptake, and on phosphorus (P) level of two associated soils was studied over three years. Five litter rates (0, 4.48, 8.96, 17.92, and 35.84 Mg ha-1; as-is basis) were applied each year to two geographically-associated soils: a Ruston fine sandy loam with no history of litter application and a Savannah fine sandy loam with high soil P due to thirty years of application. Annual forage yield and nutrient uptake increased quadratically in response to application rate. Apparent P recovery averaged 12% on the Ruston soil and 4% on the Savannah soil. Within three years, P levels of both soils were equivalent, indicating that without consideration of litter application rate, P level of even low-P soils can rapidly reach excessive levels.