The forest vegetation of 3,600,000 hectares in northeast interior Alaska was classified. A total of 365 plots located in a stratified random design were run through the ordination programs SIMORD and TWINSPAN. A total of 40 forest communities were described vegetatively and, to a limited extent, environmentally. The area covered by each community was similar, ranging from 0.29 to 4.29 percent. A large number of mixed spruce communities were described and suggested to be the result of the study area's proximity to the northern limit of black spruce (Piceamariana (Mill.) B.S.P.). Average aboveground tree biomass and productivity were estimated for each community. Values for trees ranged from 0.2 kilogram per square meter aboveground biomass and 4.0 grams per square meter per year mean annual increment for a woodland black spruce Community to 23.4 kilograms per square meter and 195 grams per square meter per year for a closed white spruce community. The potential productivity of the study area was estimated on the basis of 100-percent stocking of each community with trees. A total of 42.9 percent of the area was estimated to have potential to support commercial forests.