ANALYSIS OF SEASONAL MULTISPECTRAL REFLECTANCES OF SMALL GRAINS

Spectral reflectances of plant canopies combine cryptic information on the optical and geometrical characteristics of vegetation and underlying soil. A procedure was sought to objectively determine the components of multispectral reflectance data most directly related to plant and soil characteristics. The data set was measurements of reflectances in seven spectral bands (0. 45-2. 35 mu m), collected from planting to harvest, over one bare soil, three cultivars of winter wheat, three cultivars of spring wheat, and four cultivars of spring barley at Corvallis, Oregon. A principal component analysis (PCA) executed over the entire data set determined that the distribution of the data is largely two-dimensional. However, it did not yield indices that were related to seasonal crop development.