Long-term dynamics and controls of forest productivity in the northeastern USA

Thanks to two decades of sustained monitoring, we at the Harvard Forest are witnessing an apparent increase in the productivity of our forests.  Several studies offer potential explanations. In the northeastern USA, most forests are in the early to middle stages of development, following historic land clearing for agriculture, timber harvesting, and natural disturbances, so that even multi-decade plots capture only the aggradation phase of stand development. Increasing CO₂ levels, N deposition, and lengthening growing season interact with stand development to drive a sustained and substantial forest carbon sink in the region.