A recent study by the U.S Geological Survey (USGS) indicates a substantial decline in the number of large-diameter trees in Yellowstone National Park. Between the 1930s and the 1990s there was a 24% decline in large diameter trees.
Less large trees may cause significant changes in the habitats for many species including spotted owls, mosses, and orchids.
Jan van Wagtendonk, a former scientist at the USGS explained, “Warmer conditions increase the length of the summer dry season and decrease the snowpack that provides much of the water for the growing season. A longer summer dry season can also reduce tree growth and vigor, and can reduce trees’ ability to resist insects and pathogens.”
Large trees are also more resistant to fire, and scientists expect more frequent, intense fires due to the decrease in tree size.