Escalante Petrified Forest State Park, Nature reserve in Escalante, United States

Escalante Petrified Forest State Park is a state park 0.8 km north of Escalante, Utah, centred on a high mesa that was once an ancient floodplain. Its conglomerate cap, near the top of the Brushy Basin Member of the Morrison Formation, erodes to release colourful petrified logs, mostly red, yellow, white and black. The Petrified Forest Trail, a one-mile loop, climbs the mesa edge past trunks two feet or more in diameter.

Between 135 and 155 million years ago, large trees were buried in mud during regional floods. Groundwater slowly replaced the organic material with silica, transforming the wood into the stone specimens visible in the park today.

Local legend holds that taking petrified wood brings bad luck, a belief some folklorists link to Navajo mythology, which calls petrified wood the bones of the giant Yei Tso. The park displays "conscience letters" from visitors who returned stolen wood, describing misfortunes such as financial loss, broken bones and house fires. About a dozen returned parcels arrive each year.

The Petrified Forest Trail is a one-mile (1.6 km) loop that climbs the mesa edge to where most fossil wood erodes from the conglomerate capping. An optional 0.75-mile (1.21 km) Sleeping Rainbows loop branches off; it is steeper and requires scrambling over rocks. The park has a 22-unit campground with restrooms and a group site, and reservations can be made up to 16 weeks ahead.

The 50-foot petrified log from the Morrison Formation, added to the visitor center in 2014, is one of the most complete fossil logs known from that formation. It is displayed near the trail entrance, where the conglomerate cap of the mesa is visible.