U.S. Forest Resource Facts and Historical Trends
August 2014 | Forest Service, FS-1035
Forests in the United States store an estimated 43,126 Tg carbon in live and dead biomass and soil organic matter. Forest ecosystems in the Pacific Northwest and Northern Lake States have the greatest carbon density, often in excess of 200 megagrams per hectare.
Forest Carbon and Biomass
Forest ecosystems are the largest terrestrial carbon sink on earth and their management has been recognized as a relatively cost-effective strategy for offsetting greenhouse gas emissions. The United States quantifies forest carbon stocks and stock changes in national and international reports using data from the national forest inventory administered by the Forest Service. Forests in the United States continue to sequester more carbon than they emit each year, and combined with urban forest, and harvested wood products, offset nearly 15 percent (955 tetragrams of carbon dioxide equivalent [Tg CO2 eq.]) of total greenhouse gas emissions in 2012. An additional 270 Tg CO2 eq. was sequestered in forest ecosystems and subsequently emitted back to the atmosphere through wildfire combustion.
Urban Associated Forest
In the United States, an estimated 4 billion urban trees provide many valuable benefits based on their current composition and function. Besides the basic
value of the trees—estimated at $2.4 trillion (Nowak et al. 2002), additional benefits of urban trees include air-pollution removal and carbon sequestration. Annual
pollution removal (ozone, particulates, nitrogen dioxide, sulfur dioxide, and carbon dioxide) by urban trees is estimated at 711,000 metric tons ($3.8 billion value, according to Nowak et al. 2006) and storage of 643 million metric tons of carbon ($50.5 billion value) with a gross carbon sequestration rate of 25.6 million metric tons C per year ($2.0 billion per year) (Nowak et al. 2013).