Performance of weather-based residential irrigation controllers in a desert environment

摘要

The authors evaluated the performance of residential weather-based irrigation controllers used to irrigate tall fescue plots (Festuca arundinacea) installed in the arid Chihuahuan desert in the southwestern United States. In one experiment, Irritrol Smart Dial, RainBird ET Manager, Aqua Conserve, Hunter ET System, Weathermatic SL1600, and one manual irrigation controller programmed at 80% of historical reference evapotranspiration were tested. Compared with the manual controller, Irritrol and RainBird treatments saved 53 and 34% of irrigation water, respectively. In another experiment, Irritrol Smart Dial and RainBird ET Manager were tested for one year. Although soil moisture content of Irritrol-irrigated turf plots dipped below 50% of available soil water capacity between November 2010 and January 2011, leaf relative water content of turf grass in both treatments exceeded 85%. The Irritrol controller applied less water than the RainBird, but the ratio of variable to maximal fluorescence averaged 0.78 for both treatments, indicating that the turf grass was not stressed.