LARS Tech Report Number



A vegetation index (Kauth-Thomas greenness) was used to estimate a stress-no stress condition on corn and soybean fields in AgRISTARS segments. The procedure is an adaptation of the method developed by Thompson and Wehmanen to determine stress levels on the entire segments using Landsat spectral data. The predictions were compared to the Palmer Crop Moisture Index (CMI) and an area was assumed to be stressed when the CMI was less than -1.0. Although additional tests need to be run using years when more severe stress occurs to check the validity of the procedure, in 1978 the procedure predicted 90 and 91 percent of the stress-no stress conditions correctly for corn and soybeans, respectively.

Date of this Version

January 1982