A sun-swept corner of the Painted Desert in Arizona is home to the Petrified Forest National Park which draws more than 600,000 visitors each year. While most come to see one of the world’s largest concentrations of brilliantly colored petrified wood, many leave having glimpsed something more. The current 346 square miles of Petrified Forest open a window on an environment more than 200 million years old, one radically different from today’s grassland.
Over time, trees died or perhaps were knocked over by flood waters or wind. Rivers carried the trees into the lowlands, breaking off branches, bark, and small roots along the way. Some trees were deposited on the flood plain adjacent to the rivers and others were buried in the stream channels. Most of the trees decomposed and disappeared. But a few trees were petrified, becoming the beautiful fossilized logs we see today.