U.S. Geological Survey (USGS) quads, those navigational mainstays that cover every backwater inch of our nation, are essential to finding your way. Most are outdated, though, the land having been surveyed and the maps produced between 1940 and 1965. Mother Nature and man have since rearranged a lot of the geography with rockslides, fires, floods, and blowdowns, development, and trail rerouting. The USGS needs your help to update its more than 54,000 quads. A USGS volunteer program, the Earth Science Corps, enlists hikers to garther field information for the use in the 7.5-minute series of topos.
Contact: Earth Science Corps, (800) 254-8040; http://interactive.usgs.gov/volunteer/earthsciencecorps