Guidelines for Sampling Aboveground Biomass and Carbon in Mature Central Hardwood Forests

—As impacts of climate change expand, determining accurate measures of forest biomass and associated carbon storage in forests is critical. We present sampling guidance for 12 combinations of percent error, plot size, and alpha levels by disturbance regime to help determine the optimal size of plots to estimate aboveground biomass and carbon in an old-growth Central Hardwood forest. The analyses are based on five 100-percent inventories covering a 66-year time period. Disturbance regimes during that time included periods of grazing, low tree mortality, and high tree mortality. The size and number of plots recommended for estimating biomass and carbon changed with the type of disturbance. This information can be used to help design inventories of biomass and carbon in older forests.