AUTOMATIC CORN SOYBEAN CLASSIFICATION USING LANDSAT MSS DATA .2. EARLY SEASON CROP PROPORTION ESTIMATION

A procedure has been developed to estimate the crop proportion of corn, soybean, and others from Landsat spectral data early in the growing season. The technique requires at least two acquisitions, one of which should be before the corn Hanway stage of about 3 and another between this stage and the corn blister state. The technique thus is designed for use approximately 45-50 days into the growing season of summer crops and depends on extracting characteristics of crop type from these Landsat acquisitions. Some of the features are identical to those that can be extracted even if all possible Landsat acquisitions were available and provide automatic separation of corn and soybean. The crop proportion estimated using this technique on 18 5 multiplied by 6 nautical mile segments yielded results only slightly inferior to those obtainable when full season acquisition data were available.