Iowa State University researchers concluded from a long-term field study that poultry manure, when applied at a rate to meet the crop nitrogen (N) requirements, can reduce nitrate loss and achieve equal or better yields in corn soybean production systems. While this research focused on nitrate (NO­3-N) loss by field-tile drains (typically placed 3 to 6 feet deep), similar trends would be anticipated in Nebraska for nitrate leaching below the crop root zone and the eventual impacts on surface and ground water quality.

Spring manure applications may provide environmental and crop production advantages compared to fall manure applications. These benefits include reduced nitrogen leaching, increased crop yields, and higher phosphorus and potassium nutrient soil storage.

As we deal with frozen soils, switching to surface manure application, and the challenges of dealing with manure application during colder temperatures we need to be mindful of our application practices. While these application conditions don’t necessarily increase nutrient loss, they do increase the risk of potential loss.

When designed properly, runoff holding ponds, lagoons, and other earthen manure storage structures are sized to contain manure, process wastewater, and storm water that drain into or fall on them throughout their designed storage period. Excess precipitation, particularly chronic wet weather, can lead to concerns about storages overflowing even when they have been managed correctly.