Peak Water Requirements of Crops in Southern Idaho

Abstract

Peak water requirements for crops in southern Idaho were determined from\nfrequency distributions of evapotranspiration rates for 1-day, 3-day, 7-day,\n15-day, and 30-day averaging periods. Daily evapotranspiration for a well\nwatered reference crop (alfalfa), measured with a precision weighing lysimeter,\nand meteorological data were used to verify the calculations of daily evapotranspiration.\n\nPreviously, peak water requirements for crops in southern\nIdaho were determined from soil sampling data which represented averages\nof 10-day to 20-day periods. The frequency analysis of daily evapotranspiration\n(ET) presented in this paper provides the probable or expected peak water\nrequirements for irrigation intervals of 1 day to 30 days.