Use of thematic mapper data for the detection of forest damage caused by the pear thrips

Abstract

This study evaluates the potential of measuring, mapping, and monitoring hardwood damage caused by pear thrips in southern Vermont and northwestern Massachusetts using Landsat Thematic Mapper (TM) data. Images displayed using the TM 1.65/0.83 μ (TM5/4) band ratio, the 1.65 μ band, and the 0.66 μ band (TM Band 3), in the order of red, green, and blue, were found to clearly distinguish between high and low damage areas. Imagery employing a TM 0.83 μ band difference data set (which was produced by subtracting coregistered 1988 from 1984 0.83 μ band data) in the red plane, in conjunction with 1988 1.65 μ and 0.66 μ bands in the green and blue planes, respectively, was also found to clearly distinguish between high and low damage areas. The 0.83 μ band difference data set was used to estimate the amount of damage in the region. of approximately 0.83 million acres (0.33 million ha) of deciduous forest in the study area, 39.4% was classified as medium damage, and 9.7% was classified as high damage. © 1989.