Swan, Megan C., <i>Site Characterization and Change Over Time In Semi-Arid Grassland and Shrublands At Three Parks-Chaco Culture National Historic Park, Petrified Forest National Park, and Wupatki National Monument: Upland Vegetation and Soils Monitoring 2007-2021.</i> Fort Collins, Colorado: U.S. Department of the Interior, National Park Service, Natural Resource Stewardship and Science, 2024.