Polarization of light reflected from grain crops during the heading growth stage

Abstract The linear polarization of light reflected from different cereal crops was studied to determine its potential to remotely detect differences in crop morphology. Photographs taken at intervals of 1–4 days, over a period of 11 weeks, were used to obtain polarization imagery of four cereal grain crops. The mean value of the linear polarization of light reflected from common wheat, barley, and durum wheat canopies decreased over a 15-day period during which the crops reached 50% heading. Over the succeeding 16-day period, the mean value of polarization showed a further decrease for the barley, but an increase for both the wheats due to lodging. These results indicate that linear polarization is a useful indicator of crop differences and crop maturity.