Tongass National Forest Roads - Pre 1960

This dataset depicts roads built on the Tongass National Forest prior to 1960. This dataset is part of a larger analysis of road building and timber harvest on the Tongass National Forest, compiled for the report Scientific Basis for Roadless Area Conservation (http://www.consbio.org/cbi/projects/show.php?page=roadless/roadless.htm), pp 70-73. Road segments from a US Forest Service roads layer were attributed to the most likely decade in which the road was built, as determined by an analysis of connectivity to clearcuts on the Tongass National Forest from that decade. It was assumed that following 1960, harvests required access to mills or extraction sites, and thus roads connecting to them were most likely built within the decade prior to the clearcut. Prior to 1960, nearly all timber extraction was accomplished from the ocean shore, thus the roads built during this period were primarily for mining operations and local community transportation systems. The data are represented at a scale of 1:24000.