This report assesses past and prospective carbon stocks for 4.5 million ha of forest land in northern Wisconsin, including a baseline assessment and analysis of the impacts of disturbance and management on carbon stocks. Carbon density (amount of carbon stock per unit area) averages 237 megagrams (Mg) per ha, with the National Forest lands having slightly higher carbon density than other ownership classes. Over the last decade, carbon stocks of northern Wisconsin forests have been increasing by about one teragram (Tg) per year or 0.22 megagrams per ha per year, with most of the increase in live biomass. Harvest, wind, and fire have been principal drivers of forest carbon dynamics over the last century. For all forest types in northern Wisconsin, there is potential to increase stocking on the land by allowing more of the forested area to reach older age classes or by increasing productivity. Opportunities to increase afforestation and reduce deforestation are limited, but the potential exists for utilizing biomass energy as a substitute for fossil fuels. There are several options for private landowners to participate in carbon markets or greenhouse gas registries and receive some credit for additional actions to reduce emissions or increase sequestration of carbon. The methods used here can be adapted for use by other regions or forests to assess carbon stocks and effects of management on future carbon stocks.Cover photo by Scott Pearson.