These are all scanned photosof the Petrified Forest National Park from our trip to western parks in 2002.
Sure enough, this looks just like a fallen tree complete with root system.
The rock is surrounded for the most part by a clay-like substance that very slowly erodes away, exposing more "wood".
A pronghorn antelope. It's amazing that something this big can survive in the desert.
The painted desert from the northern part of the park.