The ORNL DAAC has released a net primary productivity (NPP) data set pertaining to the mortality of woody biomass in eastern U.S. forests.
"NPP Multi-Biome: Production and Mortality for Eastern U.S. Forests, 1962-1996" contains estimates of the annual mean aboveground wood increments for hardwood and softwood forests in 1956 counties of the 28 eastern states. The estimates are based on forest inventory data from the 1960s to the 1990s.
Visit our NPP project page to access NPP data and documentation maintained by the ORNL DAAC.