Iowa State University researchers concluded from a long-term field study that poultry manure, when applied at a rate to meet crop nitrogen (N) requirements, can reduce nitrate loss and achieve equal or better yields in corn-soybean production systems.
Nitrogen in manure requires some simple planning to insure it's given proper credit for offsetting commercial fertilizer inputs. This Water.unl.edu article offers key information for calculating N credit.
Recent heavy rains have many feedlot holding ponds full and operators looking for irrigation options to apply animal manure during the growing season. Here are some considerations for applying diluted animal manures without damaging the crop.
If manure is applied at rates equal to or less than the nitrogen (N) requirement of a crop, can manure produce environmental benefits over commercial fertilizer? This article summarizes the "Take Home Messages" from a paper summarizing 141 studies relative to the question.
Manure has value. That value may result from improvements in soil quality, increases in yield, and replacement of commercial nutrient required for crop production. This article focuses on the economic benefits of manure.
By improving soil properties manure applications can help increase water infiltration and reduce soil erosion when used in combination with other soil conservation practices. Care needs to be taken, however, in how often and how much manure is applied to avoid P loss in runoff and erosion.