What is the field irrigation requirement (FIR)?

• A. The water required to meet the evaporation needs of a crop
• B. Amount of water required to delivered at the field to meet evapotranspiration and leaching needs
• C. Amount of water required to meet the net irrigation requirements plus water lost due to surface runoff and percolation
• D. Amount of water required to meet the field irrigation requirements plus water lost in conveyance through the canal system