Landsat forest and range inventory of southeast Texas counties by administrative boundaries

A computer-aided inventory of satellite data on forest and range land in southeast Texas counties (Walker, Montgomery, and San Jacinto) was conducted. Specifically, the study was designed to develop procedures to inventory these features to determine the acreage by administrative boundaries and to evaluate the classification results. Two data sets (May and November 1973) were analyzed by means of an interactive computer process utilizing a training field classification approach. The classification results were evaluated first against historical data and again using a technique which involved sample plot checks. For the May data set, aggregating the county acreages into a single acreage per class resulted in acreages which varied less than 10 percent from the historical data. For each individual county, the class acreage estimates varied more than for the aggregate results. The acreages produced from the November classification results were unacceptable. The classification accuracies were poor when the sample plot evaluation technique was used; however, the difficulties encountered in applying the evaluation technique to Land Satellite (Landsat) data interpretation suggest that the evaluation technique was at fault rather than the classification accuracies. The study determined that pine, hardwood, and range could be inventoried by county boundaries in May. Mixed acreages could not be determined in either May or November. The forest classes and range were not spectrally separable on the November data. It was found that the county signatures obtained for each class could be used to classify acreage in the other counties; therefore, the derived signatures for pine, hardwood, and range could extend a minimum of 0.617 million hectares (1.5 million acres, the area of the three counties).