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Climate Risk Viewer - Services.aprx

U.S Department of Agriculture Forest Service and U.S. Department of the Interior Bureau of Land Management (BLM) lands contain more than 178 million acres of forest, which provide a variety of ecological, social, Tribal, and economic values. Among these values are those provided by older forests, sometimes referred to as ‘old-growth’ and ‘mature’ forests. However, neither of these terms has been consistently defined, nor has their national extent been inventoried on Forest Service or Bureau of Land Management lands by these agencies previously. These data are national in scale and present area (acres) estimates of old-growth and mature forests across all Forest Service and BLM lands. This report contains the first national inventory of old-growth and mature forests focused specifically on Forest Service and BLM lands and demonstrates that old-growth and mature forest is common (majority of Forest Service and BLM forest land) and generally widely distributed. These forests are well distributed across land use allocations. The definitions of old-growth and mature forests are presented in two forms (Tech Report Reference). Narrative frameworks are descriptive, general definitions of old-growth and mature forests that can be used consistently across geographic scales and forest types. Working definitions provide detailed quantitative criteria, using measurable structural characteristics, that were applied to specific regions and forest-types in this national-scale inventory. Forest Service and BLM lands combined contain 32.7 +/- 0.4 million acres of old-growth and 80.1 +/- 0.5 million acres of mature forest, which collectively represents 63 percent of all Forest Service and BLM forested lands and 26 percent of total surface ownership managed by the two agencies. This national-scale inventory was conducted by applying old-growth and mature working definitions to Forest Inventory and Analysis field plot data. Like all nation’s forests, old-growth and mature forests are threatened by climate change and associated stressors. The inventory and definitions for old-growth and mature forests are part of an overarching climate-informed strategy to address climate-related impacts, including insects and disease, reduce wildfire risk, and help retain carbon. Inventory results will be used to assess threats to these forests, which will allow consideration of appropriate climate informed forest management, as required by subsequent sections of EO 14072. Old-Growth and Mature forest area (acres) estimates are reported using the Fireshed Registry (https://fs.usda.gov/research/rmrs/projects/firesheds)