Scheduling the last few irrigations of the season deserves extra attention because the goal is not only to focus on keeping the crop wet enough to produce optimal yields, but also on using up stored soil water. Leaving the field a little drier at the end of the season will save irrigation costs, decrease leaching losses, improve soil conditions for harvest traffic, and save water for future years. Growers also don't want to miss out on capturing off-season precipitation.
The key to knowing the correct setting for a chemigation pump is to first determine how many acres per hour the pivot will cover at the desired irrigation application depth or rate.
Extension recommendations for calculating the amount of nitrate-nitrogen in irrigation water and optimal timing of applications to reduce the cost of nitrogen inputs in irrigated corn.