Nebraska growers share Week 2 results of their irrigation management decisions based on soil moisture sensor data, as part of a new collaboration with extension educators.
The amount and timing of irrigation applied in recent years may have very little to do with what's needed this year. Review the factors before making a decision.
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.
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.
Factors such as the amount of water a soil can hold, the amount of water a crop will use until it reaches maturity, and the maximum allowable soil water depletion should be considered when deciding the last few irrigations of the season.
I have worked with irrigation management for almost 20 years. Today most farmers are doing a better job than when I started, however many still tend to over apply water -- leaving room for improvement. That left me wondering “Why” and “What could help more farmers apply the optimal amount of irrigation water?”
The 2017 growing season started with warm dry planting conditions, followed by significant rain delays in May in many parts of the state, and a summer of intermittent weeks of hot and cool temperatures. The net result is that crops may mature over a longer period than usual this fall. Fortunately, the following procedure for making end-of-season irrigation decisions is based on crop maturity stage rather than the calendar.
In 2024, Nebraska Extension started a new collaboration with three growers located in east-central Nebraska. We installed a set of three watermark sensors at 1-, 2-, and 3-feet soil depth and the sensors were connected to datalogger (IC-10 model from Irrometer) to record and store hourly data at one-hour intervals. The data can also be accessed remotely for quick irrigation decision.
