Annual canopy cover (1973-2018) in Minnesota

These maps represent annual canopy cover from 1973-2018 for the state of Minnesota. This is an update to the original posting in February 2019 with improved maps for 2013-2015, and extended years through 2018. The canopy cover maps were created using Landsat time series methodologies with harmonization of spectral indices from the different sensors throughout the Landsat archive. The cover model was trained using dot grid intrepretation of a sample of plots from 2008 NAIP imagery, and applied across the harmonized and trend fitted Landsat spectral indices. Users should be aware that while the maps have undergone quality assessments, they have not been validated for the year outside model creation. In addition, the map years from 1973-1983 incorporate coaser resolution and lower quality Landat MSS imagery, thus confidence in these years of cover data may be lower than the remainder of the time series. For the purpose of these maps, we consider cover in a functional sense, meaning that large woody shrubs may be grouped with true tree species in the representation of cover estimates.