Short-term effects of poultry litter form and rate on soil bulk density and water content

Poultry litter is an organic amendment that has been used successfully as an alternative nutrient source to inorganic, commercial fertilizers. Poultry litter also has the potential to improve other aspects of soil quality. However, few field studies have been conducted to ascertain the effects of poultry litter on soil physical properties. The objectives of this study were to evaluate the short-term effects of poultry litter form (i.e., fresh vs. pelletized) and rate on soil bulk density and water content and early-season stand development in three fine-textured soils of the Mississippi River Delta region of eastern Arkansas that are commonly cropped to rice (Oryza sativa L.). Six litter rates were used representing a range of total nitrogen (N) rates. Soil samples were collected from the 0- to 10-cm depth between four and six weeks after litter application and incorporation for bulk density and volumetric water content determination. Leaf area index was measured as an indicator of early-season stand development. Litter form did not affect soil bulk density, water content, or leaf area index in two silt loams, and a silty-clay soil. In contrast, soil bulk density decreased significantly (p < 0.01) as litter rate increased and leaf area index decreased as bulk density increased in one silt-loam soil, but was unaffected by litter rate in the other silt-loam and silty-clay soil. Litter rate generally did not affect soil volumetric water content, but results indicate that the effects of litter rate may be manifested more at relatively low soil water contents. The results of this study demonstrate that poultry litter has positive short-term effects on physical properties of fine-textured soils. These results are agronomically significant for many crops in terms of the potential for creating a less compacted seedbed for seedling emergence, improved stand development, and ultimately increased crop yields.