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Conserving America's National Parks shares the status of conservation challenges and successes in America's 408 national parks. Rising sea levels, collapses of coral reefs, loss of wildlife species, droughts, severe fires, non-native species, and climate change are among the many challenges defining contemporary conservation at the 100-year centennial of the National Park Service in 2016. However, thrilling outcomes of active conservation projects, such as the largest removal of river dams in U.S. history, provide hope for the future of parks. Written for readers with diverse backgrounds,...

Gambel oak (Quercus gambelii) is a key deciduous species in southwestern ponderosa pine (Pinus ponderosa) forests and is important for wildlife habitat, soil processes, and human values. This report (1) summarizes Gambel oak's biological characteristics and importance in ponderosa pine forests, (2) synthesizes literature on changes in tree densities and fire frequencies since Euro-American settlement in pine-oak forests, (3) suggests management prescriptions for accomplishing various oak management objectives (for example, increasing diameter growth or acorn production), and (4) provides an...