Vegetation history based on pollen records from three small lakes on different geological substrates in Yellowstone National Park

Vegetation history based on pollen records from three small lakes on different geological substrates in Yellowstone National Park.   Blue is open vegetation, light green is parkland, dark green is forest.  Top plot is from Slough Creek Pond, in a present grassland area dominated by glacial and lake sediment in the northeast part of Yellowstone National Park.  Middle plot is from Cub Creek Pond in the Absaroka volcanics on the east side of Yellowstone National Park.  Bottom plot is from Cygnet Lake in the Central Plateau rhyolites in the center of Yellowstone National Park.  Figure by Cathy Whitlock, Montana State University.