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Poultry litter is commonly land applied as an organic fertilizer on crop and pasture land. However, the high variability in physical characteristics of litter, especially moisture content and bulk density makes it difficult to maintain uniform distribution when using spinner-disc spreaders for litter application. A study was conducted to understand the effect of litter bulk density on conveyor discharge rate and spread pattern for a spinner-disc, litter spreader. A series of conveyance and uniformity tests were performed to evaluate density effect on litter metering and application uniformity. Two loads of litter (A and B) at different moisture contents (32% and 28%, respectively) and bulk densities (26 and 30 lb/ft3, respectively) were used in this study. Different spreader and rate controller settings (two gate heights: 7 and 13.75 inches, four application rates: 1556, 3057, 3113 and 6115 lb/ac, two correct densities: 26 and 30 lb/ft3, and three incorrect densities: 22, 26 and 34 lb/ft3) were established as treatments for conducting the tests. Actual and theoretical discharge rates were calculated and compared for conveyance data analysis whereas mean single-pass and standardized distribution patterns were generated and compared for field tests. Results indicated that incorrect density treatments generated high rate errors (>15%) during conveyance tests. Field application rates were also outside the considered 10% acceptable limits for both litter types (A & B). The computed CVs for most of the field tests ranged from 23.4% to 30.3%. For both litter types, the central peak of the single-pass patterns at different density treatments varied with actual application rate (mass flow). Standardized patterns at different density treatments for same litter type were found to be statistically different (p>0.05) at a few transverse positions across the swath. The occurrence of high rate errors along with observed differences in distribution patterns at a few transverse positions were due to incorrect density treatments applied in the Spreader Control Software. The results indicated the importance of determining and using the correct density value within a spreader, rate controller for accurate application with spinner-disc spreaders.