Pasture conservation management effects on soil surface infiltration in hay and grazed systems

Abstract

Diminished water quality in the mid-southern United States is often resultant from improper poultry litter management in pastures. Grassland best management practices (BMPs) need to be identified that increase soil-water infiltration. Therefore, the objective of this research was to evaluate infiltration rates based on pasture BMPs (aeration timing, subsurface banded litter, and gypsum) in hay and grazed systems from 2018 to 2019. Twenty minute falling-head infiltration measurements were conducted at zero, one, and three months following management implementation in hay (Experiment 1) and grazed (Experiment 2) systems. Management effects on forage quality and yield were also measured in the hay system. In Experiment 1, infiltration differed across treatments and by month following BMP implementation. Averaged across months (Experiment 1), the greatest infiltration rate occurred for June aeration, which was the only month when aeration increased infiltration compared to the control under hay conditions. In Experiment 1, averaged across treatments, greatest infiltration occurred three months following treatment implementation. Gypsum had no effect (P > 0.05) on infiltration rates. Under grazed conditions (Experiment 2), infiltration rates differed by treatment and month and were greatest one- and three-months following June aeration, three months following April aeration, and three months following subsurface banded litter treatment. February aeration and subsurface litter applications resulted in lower (P < 0.05) infiltration rates than the control in grazed systems. Across months for the grazed experiment, June aeration had the greatest (P > 0.05) infiltration rates. Among all BMPs temporally, June aeration improved soil-water infiltration under both hay and grazed systems. Therefore, pasture aeration implemented in June following broiler litter applications can likely reduce nutrients in surface runoff in grassland systems, regardless of management (hay or grazing) compared to traditional surface-broadcast only practices.