New crop coefficients estimate water use of vegetables, row crops

Portable Bowen ratio instruments constructed and calibrated against lysimeters were used to develop crop coefficients to predict the water requirements of vegetable and row crops. Evapotranspiration (ET) was measured in crops at different stages of growth. A direct ratio between the crop a a reference grass was used to calculate a crop coefficient under different levels of ground cover. As ground cover increased, most of the crop coefficients increased as well.