• Disturbances (wildfire, insects, and others) are often a vital part
of healthy forest ecosystems,
but the increasing extent and severity of biotic and abiotic forest disturbances pose increasing challenges to ecological, economic, and social dimensions of forest sustainability. Over the past 20 years, wildfire intensity and area burned have trended upward at the national scale. Although national-scale, insect-induced
tree mortality has decreased since spikes in the 2000s, insects remain the principal biotic cause of tree mortality in the U.S., particularly in the Pacific Coast
and Rocky Mountain Regions. The increased temperatures and drought attributed to climate change, combined with increasing forest density and insect-induced tree mortality, can create the conditions for increasing wildfire severity and extent.
• Although forests continue to serve as a carbon sink at the national level, forests in several states in the Intermountain West are producing net carbon emissions at the state scale largely owing to forest disturbance activity. Forestland, harvested wood products (HWP), woodlands, and urban trees represent the largest net carbon sink in the U.S., nationally offsetting around 10–15% of total domestic emissions annually.
• Forest-protected rivers and streams are in relatively good condition in the U.S., and previously high levels of acidification observed in forest soils have continued to decrease in recent years. Best management practices (BMPs)
for forests focused on reducing the negative impacts of forest management on water and soil resources are widely implemented in the U.S. and have been shown to be effective. Although nationwide assessments of water bodies paint an overall picture of poor condition, there is evidence that forest-buffered public water supplies are in good condition.
• The wood industry in the U.S. has rebounded with the recovery in the broader economy over the past decade; however, this rebound had been strongest in portions of the South Region and wood production levels remain below their peak. Per capita consumption of wood and paper products decreased 21% since 1965 and production levels are still far below their peak in the late 1980s. Employment in the wood and paper products sectors declined 40% since its most recent peak in 1998.
• Forest recreation is a principal forest ecosystem service but may be increasingly constrained by disturbances (notably wildfire and smoke) and maintenance backlogs on roads, trails, and facilities on Federal lands. Revenues from forest-based ecosystem services have continued to increase, and non-timber forest products remain important sources of revenue but are more difficult to track over time.
• Sustainable forest management is pursued in the U.S. through an expanding range of legal, institutional, and economic approaches developed and applied across multiple scales, ownerships, and actors. These approaches address the ecological, economic, and social dimensions of forest sustainability and increasingly rely on forest-focused collaborations and partnerships that share a common recognition of the importance of forest restoration, wildfire risk reduction, multiple uses, and local forest-based livelihoods. Institutional capacity for traditional forest management activities has declined in some areas, notably forestry research.