225 million years is about the time it takes to turn large trees into stone, uplift, and expose them through erosion. To create the petrified forest, first there was a sub-tropical forest with dinosaur-like crocodiles hunting through the jungle. Before tectonic changes and the split of land masses, this area would have actually been as far south as Panama. There was a flood and massive trees sunk to the bottom of a floodplain. Covered by sand and ash, the logs did not decay and instead, with silica-laden groundwater, crystalized into quartz. Other colorful crystal patterns came from iron and other minerals. Polished into beautiful pieces, the petrified wood was highly sought after until 1906 when Theodore Roosevelt set aside protected stands of the forest.
Fyi - the earth is 4.6 billion years old. Microscopic forms of life appeared about two billion years ago. These trees date to the Triassic period around the age of dinosaurs so they are still relatively young!
