BiotechMashup

(United States Geological Survey) Large trees have declined in Yosemite National Park during the 20th century, and warmer climate conditions may play a role. The number of large-diameter trees in the park declined 24 percent between the 1930s and 1990s. USGS and University of Washington scientists compared the earliest records of large-diameter trees densities from 1932-1936 to the most recent records from 1988-1999.