LARS Tech Report Number



Multispectral scanner data were collected in two flights over a light colored soil background cover plot at an altitude of 305 m. Energy in eleven reflective wavelength bands from 0.45 to 2.6 µm was recorded by the scanner. Four growth stages of maize (Zea mays L.) were present at the time of each over flight, giving a wide range of canopy densities for each flight date. Leaf area index measurements were taken from twelve subplots at the time of each overflight, and were used as a measure of canopy density.

Ratio techniques were used to relate uncalibrated scanner response to leaf area index. The ratios of scanner data values for the 0.72 to 0.62 µm wavelength band over the 0.61 to 0.70 µm wavelength band were calculated for each plot. The ratios related very well to leaf area index for a given flight date but could not be generalized between data from different flights because of uncertainty in scanner response on different dates. The results indicated that spectral data from maize canopies could be of value in determining canopy density.

Date of this Version

January 1972