Click on “Download PDF” for the PDF version or on the title for the HTML version.

If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.

Abstract. Irrigation helps grow agricultural crops in dry areas and during periods of inadequate rainfall. Proper irrigation could improve both crop productivity and produce quality. For high density apple orchards, water relations are even more important. Unit today, most irrigation in tree fruit orchards is applied based on grower experience or simple observations, which may lead to the waste of over-irrigation or the ineffectiveness of under-irrigation. The decision making for irrigation at proper timing for appropriate periods is critical. A series of studies were conducted at a high density apple orchard to investigate the feasibility of irrigation scheduling using sensor information. Four different sensing systems were used to calculate the water status of the crop or soil, including weather data, thermocouple sensor, soil water content sensor, and soil water potential sensor. Then the daily Evapotranspiration (ET), Crop water stress index (CWSI), soil water content threshold, and soil water potential threshold were calculated or identified for scheduling the irrigation. The outcomes from this study provided guideline information to the automated irrigation system with precision scheduling. At last, future improvement and the possibility of implementation were also discussed.