Barbara S. Poore Holly K. Caro Greg D. Matthews B. Wolf Eric 2011 Since 1994, citizen volunteers have helped the U.S. Geological Survey (USGS) improve its topographic maps. Through the Earth Science Corps program, citizens were able to "adopt a quad" and collect new information and update existing map features. Until its conclusion in 2001, as many as 300 volunteers annotated paper maps which were incorporated into the USGS topographic-map revision process. application/pdf 10.3133/fs20113103 en U.S. Geological Survey Volunteer map data collection at the USGS reports