Wisconsin is one of the nation’s leading poultry producers. Manure generated by poultry has the potential to negatively impact the state’s water resources if not properly managed. A common management practice associated with poultry manure handling is “headland stacking”. Headland stacking involves temporarily storing poultry manure on field edges until the field is available for manure spreading (after the crop is harvested). As defined by a Wisconsin Department of Natural Resources (WDNR) WPDES permit for a poultry operation, headland stacking occurs when poultry manure is piled in fields for 11 to 365 days prior to spreading. In practice, most headland manure stacks remain in place fewer than 3 months.