Working to steer this effort closer to reality are scientists Kevin Bronson and Kelly Thorp of ALARC’s Water Management and Conservation Research Unit.

Unit leader Bronson says, “ALARC’s mandate is field-scale water management research in terms of improving water use efficiency. We want to maintain high productivity but reduce the inches or acre feet of water used to grow crops, especially cotton.”

Each year, ALARC researchers tap technology to study water use efficiency in crops grown in the Grand Canyon State, including experimental crops. For cotton, 2016 is the third year of sprinkler field trials and the first year of buried drip field trials conducted by Bronson and Thorp.

Variable rate irrigation

The research duo is using variable rate irrigation (VRI) with sprinklers in a 16-acre field and drip line buried eight inches deep in a nearby four-acre field.

The overhead sprinkler system includes a Lindsay Zimmatic linear move sprinkler system with six spans and an overhang, and retrofitted with a variable rate irrigation system.

Thorp explains, “With an overhead sprinkler system we don’t need bed shaping and related tillage.”

The overhead sprinkler system is managed using precision agriculture tools to provide timely, variable applications across the field, including remote sensing, computer modeling, and other tools from their technology bag.

Thorp says, “VRI allows us to manage the field so we can explicitly show how cotton responds to different water rates and timings from June through August.”