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Northern tamarisk beetle impact and classification maps, Grand Canyon National Park, Arizona

April 12, 2021

These data are satellite image-derived, classification maps of tamarisk (Tamarisk spp.) along the Colorado River in Grand Canyon National Park from river km 315 to 363, approximately from Parashant Canyon to Diamond Creek tributaries. The classification maps are published in TIF raster format. Two maps are published: 1) a classification of healthy, defoliated, and tamarisk canopy dieback from the tamarisk beetle (Diorhabda carinulata) in May 2019, and 2 a classification of healthy and beetle-impacted tamarisk in August 2019. Tamarisk was mapped using a Spectral Angle Mapper supervised classification derived from 2 m resolution, multispectral WorldView-2 imagery, with an overall accuracy of 80.0% in May 2019 and 83.1% in August 2019. The area of healthy, defoliated, and canopy dieback totaled 43.6, 2.9, and 18.2 ha, respectively, in May, and the area of healthy and beetle-impacted tamarisk totaled 19.1 and 35.6 ha, respectively, in August.