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Best Management Practices – Irrigation Scheduling using Water Balance

Quick fact sheet to support irrigation scheduling. 

  • A simple method to tracks soil water deficit by accounting for all water additions and subtractions from the soil root zone.
  • Crop water consumption or evapotranspiration (ET) accounts for the biggest subtraction of water from the root zone while precipitation and irrigation provide the major additions.
  • The soil in the root zone has an upper as well as a lower limit of storing water that can be used by crops.
  • As the crop grows and extracts water from the soil to satisfy its ET requirement, the stored soil water is gradually depleted.
  • Crop evapotranspiration can be obtained from the Colorado Agricultural Meteorological Network (CoAgMet) or by using atmometers.