Wildland fire has been an integral part of the landscape of the conterminous United States for millennia. Analysis of contemporary and pre-industrial (~ 200 - 500 yr BP) conditions, using potential natural vegetation, satellite imagery, and ecological fire regime information, shows that wildland fires burned 35 - 86 x 106 ha (megahectares) annually in the pre-industrial era, consuming 530 - 1230 teragram (Tg) of biomass. At present, in comparison, 5 - 7 Mha/yr burn, consuming 77 - 189 Tg of biomass annually. If historic fire regimes were restored to non-urban and non-agricultural lands today, 18 - 43 Mha would burn annually, consuming 285 - 602 Tg of biomass. For each era, 11 biomass (wildland and agricultural) burning emissions were estimated, and... |