Soil and plant quality of a vegetable soybean crop following application of different types of poultry litter

Poultry litter, as a fertilizer, may be beneficial to soil quality and soybean crop production. Poultry litter adds organic matter to the soil and nutrients that are required by plants. Research was conducted in 2005 and 2006 to study the effects of different types of poultry litter (composted, formulated or pelletized) on soil and plant quality of a vegetable soybean crop. Nutrient availability (N and P), soil pH, and electrical conductivity generally increased from application of formulated or pelletized litter ( P < 0.05), while composted litter only increased P availability. Microbial biomass and enzyme activities rarely showed immediate responses and were highly variable. No improvements were observed in plant growth or seed quality. Results indicate that composted litter may be a better option over formulated or pelletized litter because it may increase P availability in P deficient soils without drastically increasing inorganic N concentrations or soil pH.