SoyWater: An Irrigation Decision Aid for Nebraska Soybean Producers

A new UNL website offers soybean producers an easy-to-use decision aid for optimizing irrigation efficiency and energy use.

SoyWater, available at soywater.unl.edu, asks a few, simple questions specific to the field and then provides daily estimates of crop water use and soil water status.

Users log on and after just a few mouse-clicks, SoyWater provides a table of real-time, actual daily weather data for computing daily crop water use from planting (or emergence) to the day before producer log-in. It then uses historical weather data to compute daily crop water use from the day of log-in to the day of expected crop maturity.

The daily weather data is from a weather station of the Automated Weather Data Network (AWDN) maintained by the High Plains Regional Climate Center (HPRCC). (SoyWater automatically identifies the weather station nearest the producer’s field.) During the season, the producer will log in to SoyWater to input the date and amount of local rainfall and any irrigation applications.

Based on this information, SoyWater will highlight the projected date when the first (or next) irrigation should be scheduled and projects the dates of specific soybean vegetative (V-) and reproductive (R-) growth stages. SoyWater can be useful to both rainfed and irrigated soybean producers interested in predicting the date of a V- or R-stage. This information also can be useful when making other crop management decisions for a particular soybean field, such as when the effectiveness of a herbicide or fungicide depends on application at a specific growth stage.

Meeting the Information Needs of Soybean Producers

The UNL SoyWater research team is pleased to offer this website service so soybean producers no longer have to face the drudgery of hand-calculating daily crop water use and soil water balance. This website does all the calculations so a user can get real-time estimates of crop water use.

SoyWater can help producers make better irrigation scheduling decisions, minimizing the amount of irrigation water needed for optimal crop production. In turn, this will reduce seasonal water withdrawals from the Ogallala Aquifer and lessen energy costs for pumping. While SoyWater is not an absolute indicator of when to irrigate, it’s a decision-aid tool that producers can use along with their skills and expertise to decide when to irrigate and how much to apply.

For more detailed information about SoyWater, click here.