Schrader-Patton C, Grulke, N.E., Dressen M. E. 2016. Characterizing a forest insect outbreak in Colorado by using MODIS NDVI phenology data and aerial detection survey data. Gen. Tech. Rep. PNW-GTR-940e. Portland, OR: USDA Forest Service, Pacific Northwest Research Station. 35 p. TreeSearch link.
Satellite derived NDVI (normalized difference vegetation index) data at a resolution of 250 m were used to assess insect outbreak damage to forests on the Medicine Bow-Routt National Forest in Colorado. To translate the raster based information into a form useful to forest managers, maps were created that show intensity and time of insect disturbance, aggregated by forest stand polygon. Because NDVI loss is applied to forest stands, this reduction in greeness can be associated with stand species composition, canopy cover and tree size. This rapid assessment provides managers with a synoptic look at events such as insect outbreaks and droughts. Mortality patterns from these processes can help managers prioritize forest stand monitoring and salvage efforts.