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Arizona’s Petrified Rainbow Wood

“Petrified Wood”, “Rainbow Wood”

Araucarioxylon arizonicum is the species most associated with Arizona’s petrified wood.

Adopted in 1988 as the Arizona State Fossil

Lived in the early Permian and late Triassic, 295 to 201 million years ago

Fossils are found in the Chinle Formation in desert badlands of northern Arizona and adjacent New Mexico and Chemnitz petrified forest in Chemnitz, Germany. The trees probably ranged much farther.

Habitat: Arizona during the Triassic was a flat tropical plain in the northwest corner of Pangaea.

Fun Fact: Most Arizona petrified wood can be found in northern Arizona, in and around Petrified Wood National Park.

Fun Fact: There are many species of trees that have been fossilized and are called “petrified wood.” Sometimes the wood is preserved so well that that cells and other microscopic structures of the original wood can still be seen in the stone.

Classification: A conifer, like pine trees. The closest living relatives are 41 species living almost exclusively in the southern hemisphere.

Described: byFrank Hall Knowlton in 1889

Height: 200 feet (60 meters)

Diameter (trunk): 2 feet (60 centimeters)

Fun Fact: “Araucarioxylon arizonicum” is actually three closely related species, perhaps more. The correct names are Pullisilvaxylon arizonicum, Pullisilvaxylon daughertii, and Chinleoxylon knowltonii. Scientific work continues to determine how many species there really are. At least 14 species have been found within Petrified Forest National Park.

Among the nearest living relatives to Araucarioxylon are the Monkey Puzzle Tree, and the Norfolk Island Pine. Both are used as lanscape plants, and many Norfolk Island Pines are sold during the winter holidays.

Monkey Puzzle Tree or Chilean Pine, Araucaria araucanaNorfolk Island Pine, Araucaria heterophylla