Fig. 6. Coefficients of determination (r²) for the linear relationship between (a) canopy reflectance and total leaf nitrogen, (b) reflectance at 415 nm divided by reflectance at wavelength indicated by the horizontal axis, and (c) reflectance at 710 nm divided by reflectance at each wavelength. All plot means of spectral reflectance and chlorophyll collected during the two-month study (n = 22) were included in the correlation analyses.