The ecological importance of trees in forest ecosystems extends well beyond their biological life in both space and time. When trees fall or shed components such as branches, downed and dead woody material (DWM) is created that provides critical substrate for the establishment of vegetation, habitat for wildlife species, and nutrients for a variety of forest ecosystem functions. The benefits of DWM in forests and, indirectly, to society, can be at odds with the fact that the material may also hinder forest management activities, provide habitat for forest pests, and increase wildfire risk. The Forest Inventory and Analysis (FIA) program has been sampling downed and dead woody material since 2002. Until recently, there has not been sufficient DWM data to obtain consistent national estimates that meet the precision standards established by the FIA program. For this reason, downed and dead woody material estimates were modeled using geographic area, forest type, and live tree carbon density. Thanks to FIA's sampling of DWM, most states now have a complete cycle of data and for the first time field measurements, not models, provided estimates of downed and dead woody biomass and carbon stocks for the FIA program and for DWM carbon estimates in the National Greenhouse Gas Inventory report. The researchers believe that the transition from purely model-based estimates of DWM to field-based estimates will result in a more accurate DWM inventory and better measure DWM's sensitivity to human-induced disturbances and events resulting from a changing climate.