Quartz Petrified Wood at The Wagner Free Institute of Science

Title: Quartz Petrified Wood

Year: 200 million years ago

Material: Petrified Wood

Creator: Nature;  A tree in Arizona’s Petrified Forest National Park

Collection: The Wagner Free Institute of Science

Did this tree look like this?

Once a tree, now a rock, this beautiful hunk of petrified wood has undergone quite a transformation over the last, oh, 200 million years or so. Petrified is from the Greek root petro meaning "rock" or "stone;" literally "wood turned into stone." Basically, this tree slowly morphed to stone through permineralization, a process that occurs when a tree’s interior is replaced by the minerals from the surrounding soil, but the shape of the tree remains. It is now a fossilized version of its former self.

In order for this to occur, there must be some ideal conditions. A tree falls. It becomes buried in sediment, creating an oxygen-free environment, which prevents the tree from decomposing. As time passes, minerals in the surrounding sediment enter the tree’s cells. These cell walls decay and are replaced by a stone mould, often silica-quartz. Make sense? My grandfather was a geoscientist, but I unfortunately did not inherit his science smarts, so if you need a more thorough explanation, check this out. 

This object was given to the Wagner Free Institute of Science by John Goodhart Rothermel, who directed the Institute from 1903-1924. An avid explorer and collector, he contributed many specimens to the collection.  Rothermel discovered this specimen during a visit to Arizona’s petrified forests the summer of 1915, shipped it back to the Institute, and it was been on display ever since. The area where this specimen was found was declared a National Park in 1962 (appropriately named, The Petrified Forest National Park) and is considered to have one of the largest, most colorful collections of petrified wood in the world. 

Geologists, archeologists, naturalists, environmental biologists, artists, National Park Rangers and Park visitors might all be interested in this object. Knowing of my love of old trees and National Parks, a friend had told me about it prior to my visit, so I was on the prowl. I looked and looked (and even asked a staff member who didn't seem to know what "really old tree" I was talking about). Just when I was about to give up, there it stood, in the southeast corner of the room, hiding under a staircase. 

This object is presented in a glass case that sits atop a wooden stand. While there are other fossils from trees and other plants in a case far across the room, this one stands alone. Nearby cases include shells, many of which William and Louisa Wagner collected on their honeymoon. Just as the tree was once alive with roots and cells and leaves, these shells formerly contained a fragile, living creature inside. Large birds (also formerly living creatures) and nests are also within view. One could make an association between these animals and this ancient tree, as many birds call trees home. Given its origins in the Petrified National Forest however, any modern birds would not yet have existed when this tree stood, but perhaps a few theropod dinosaurs hung out in its branches?

As you can see from the images above, this object is accompanied by very little descriptive text. If the label did not identify this specimen as petrified wood, visitors, particularly those without a strong science background, might form a different narrative about this object. One might assume it has “always” been a rock. Without an understanding of how rocks are created, one might guess that this pretty rock was formed within the last few centuries. While its beauty is apparent, its age and compelling narrative are not obvious to the average viewer. Independent research and/or insights from an expert (such as the Wagner’s Archivist) are useful in order to fully appreciate this specimen. Unfortunately, without one or both of these information-gathering methods, many visitors might not express an interest in this object or at the very least, overlook it because of its placement within the gallery.

Book Info Here

To enrich my understanding, I could read more about the Petrified Forest National Park online, or check out Petrified Forest: A Story in Stone by Sidney Ash or When Wood Turns to Stone: The Story of the Arizona National Petrified Forest by 

K.S. Tankersley. It might also be fun to explore other species that likely existed during this tree's life. 

Book Info Here

Researching online, I was interested to learn that this object was highlighted through a special program in September of 2011, as part of the International Year of Forests. During “Fantastic Forests,” visitors could participate in an interactive natural history lesson, a forest-themed scavenger hunt and outdoor activities in the pollinator garden.  Attendees learned about types of forests and their surrounding ecosystems, why they are important, and how they can be protected. Personally, I would like to declare every year to be an International Year of Forests and would implement a program similar to  “Fantastic Forests” on a permanent basis. Knowing that this institution sees a primarily urban audience, I would also create a special program about the importance of city trees. Collaborating with The Pennsylvania Horticultural Society and Tree Philly, this event could include a presentations and interactive demonstrations about tree identification, tree care, and how to plant street and yard trees. In advance of the event, participants could sign up for a free street or yard tree and pick it up at a nearby location in Fairmount Park after the event (of course, this would take a lot of coordination).

 

While the scientific processes that transformed this wood to stone are a little complicated for me to comprehend, its beauty speaks for itself. I am eager to see more. Next stop, The Petrified Forest National Park.