Dr. Glen Ritchie of the University of Georgia has used model PS-100 spectroradiometer to take reflectance measurements in cotton fields and estimate defoliation. Chlorophyll gives plant leaves a reflectance spectrum characteristically different from that of soil. Reflectance measurements can be reported in µmol m^-2 s^-1, W m^-2, or as a relative value.

View poster presented at ASA meeting.