BIOPHY depicts boundaries of 15 Biophysical Regions in Maine at 1:250,000 scale. The regions were developed in a statewide classification (McMahon, 1990) by Janet McMahon who examined spatial patterns in a number of mapped environmental variables. These patterns were statistically evaluated using canonical correspondence analysis. Ordinations of 1,966 samples, 95 woody taxa, and 22 environmental variables, reveal that both biophysical regions and woody species vary primarily along a climatic gradient of increasing annual temperature, potential evapotransportation, heat sum, and other factors associated with temperature. Boundaries were mapped for 'Biophysical Regions of Maine' at 1:700000 scale by Maine State Planning Office (MESPO) staff in 1990. Maine Office of Geographic Information Systems (MEGIS) staff digitized these boundaries from the 1990 publication, recompiling the data onto a 1:250,000 scale base. The state boundary and coastline were extracted from the coverage METWP250. Each region contains attribute fields extracted from a summary table on the 1990 publication. The coverage was renamed from BIOPHY250 to BIOPHY in 2001.