Louisiana: petrified palm wood (state fossil)

Louisiana's official state fossil is petrified "palm" wood assigned to the botanical form genus Palmoxylon. This means that the structure of the wood resembles that of modern palms, although it may or may not be closely related to them.

This wood is the petrified remains of trees that grew on the Gulf Coastal Plain during the Oligocene Epoch, around 30 million years ago. At that time the shore of the Gulf of Mexico was further north than it is now, which explains why the wood is usually found in the more northern parishes of the state, frequently in the Catahoula Formation.

The petrified wood formed when a tree died and was buried by sediments. Minerals in the groundwater permeated the wood, replacing the original organic matter and turning the wood to stone. The main mineral is silica, but trace elements in the silica impart a variety of colors to the petrified wood. Artifacts made of petrified wood found at Paleoindian sites indicate that Native Americans have known of these deposits for thousands of years.

Because of its ubiquity and popularity with collectors, petrified palm wood was designated the Louisiana state fossil by Act No. 362, passed as Senate Bill No. 155 by the legislature, and signed by the governor on July 31, 1976.

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Louisiana symbols

Petrified Palm Wood