Bermudagrass Establishment on Infertile Soil: Growth and Phosphorus Losses with Poultry Litter Ash and Triple Superphosphate

Abstract

ABSTRACT Lower solubility of P in poultry litter ash (PLA) than conventional P fertilizers such as triple superphosphate (TSP) may reduce P losses in drainage and runoff, however, lower P solubility may reduce its efficacy as a P source. The mineral composition of PLA and acid-induced P release from it were determined. Effects of PLA, TSP or no P fertilization at different initial soil pH values (5, 6 or 7) on the establishment of common bermudagrass (Cynodon dactylon L.) on a representative coastal plain soil (Ruston; fine-loamy, siliceous, semiactive, thermic Typic Paleudults), and P leaching and runoff loss were determined using packed soil columns with incorporated fertilizer (TSP supplemented with K, Ca and Mg to equal that in PLA). Soil columns at near water-holding capacity were seeded, watered daily, and fertilized with N. Yields and tissue concentrations of P, K, Ca and Mg were measured eight and 16 weeks after planting, and total and dissolved reactive P in leachate and in runoff during simulated rainfall were determined. Yields and tissue concentrations were greater where fertilized but there were no consistent differences between PLA and TSP. Leaching of P was negligible for TSP besides PLA due to high P sorption capacity of the soil; however, P runoff losses significantly decreased TSP > PLA > control. Given no disadvantage of PLA compared to TSP on bermudagrass establishment but evidence for reduced loss in runoff, tentative results should be confirmed using field plots.