Figure 1. Spectral response curves for PE 1 are reported for predrought (30 July 2004), early drought (5 Aug. 2004), middrought (17 Aug. 2004), and late drought (1 Sept. 2004). Data represent average reflectance (%) along the y axis and wavelength (485–1650 nm) along the x axis for each treatment (211CC, 375CC, 511CC, 522CC, and AT201).