Petrified: Shannon Woods by Petrified Wood Courtesy & © Shannon Rhodes, Photographer
Shannon Woods by Petrified Wood
Courtesy & © Shannon Rhodes, Photographer
“Charlie climbed onto the bed and tried to calm the three old people who were still petrified with fear. “Please don’t be frightened,” he said. “It’s quite safe. And we’re going to the most wonderful place in the world!”

Author Roald Dahl uses the word petrified as being motionless, stonelike, frightfully frozen, as he describes Charlie Bucket’s puzzled grandparents and his own excitement about a trip to Mr. Willy Wonka’s Chocolate Factory. Utah’s San Rafael Swell rates as one of the most wonderful places in my world, and not because of an abundance of chocolate or gleeful oompa loompas. Beneath the towering spires on my bucket list-quest to see desert bighorn sheep in the wild, I’ve wandered among the petrified wood fragments scattered in the desert sand, so many that I almost forget to appreciate them for what they are. Petrified wood is a fascinating fossil, colorful evidence that what is now desert was once lush forest. We’ve set aside places like Petrified Forest National Park in Arizona, and Utah’s own Escalante Petrified Forest State Park boasts something like five and a half million tons of fossil wood.

When I adventure through and research Utah’s geologic history, it makes sense that the Chinle layer is a major host rock for petrified wood and uranium in the San Rafael Swell. Let’s go back in time to find out why: Over 100 million years ago, an ancient sea covered much of Utah. The San Rafael Swell was a large island where tall conifers lined its riverbanks and dinosaurs slogged through its swamps. Evidently, as understood by radiation specialist Ray Jones in a 1997 Deseret News feature titled “Hot Spot,” “Uranium isotopes dissolved in water tend to bond chemically with decaying material, like branches and logs.” Uranium prospectors in the early 1900s would follow petrified branches in the San Rafael Swell to uranium ore-bearing larger stumps buried with almost Geiger-counter precision. It’s no wonder that uranium mines dot the hills and debate continues about mineral resource rights in the area.

Petrified Wood Courtesy & © Shannon Rhodes, Photographer
Petrified Wood
Courtesy & © Shannon Rhodes, Photographer
The Greek root petro means “rock,” so petrified wood is prehistoric vegetation “turned to stone.” Permineralization is this process when minerals replaced the organic tree material when the organism was buried in water-saturated sediment or volcanic ash. Without oxygen, the logs, stumps, tree rings, knots, and even bark were preserved, giving paleobotanists clues to relationships between prehistoric plants and those we have today. According to Dr. Sidney Ash, we even find evidence of busy bark beetles in the petrified specimens in the Wolverine Petrified Wood area of Grand Staircase-Escalante National Monument.

In “Petrified Wood: Poetry Written by the Earth” released by the Myanmar Geosciences Society, I learn there are sacred shrines erected in Thailand’s petrified forests attracting visitors praying for protection. Thai legend states that touching petrified wood will give a person long life. Charles Darwin also mentioned his fascination with prehistoric plants and upright fossilized tree stumps in his naturalist journals during his expeditions, and we know he gathered and catalogued specimens. It may be bad luck, however, to move a petrified fossil from where it lies, a superstition shared by many Escalante Petrified Forest State Park visitors who have ignored the “leave only footprints, take only photographs” warnings. It seems that the park rangers receive packages from petrified offenders returning the fossil shards with apologetic notes, wishing they’d just admired the artifacts in their natural Utah settings. I’ll admit that, had I been able to lift the massive specimen I stumbled upon while I was Behind the Reef this spring, I might have been tempted to take it home. The magic for me, though, is imagining a dense forest once where cactus and rabbit brush now thrive. Whether one uses the word to mean frozen as stone from fear or geologic processes over time, and whether one is searching for uranium or a glimpse into prehistoric biomes, petrified wood is a symbol of long-lasting wonder.

I’m Shannon Rhodes, and I am wild about petrified Utah.


Images: Courtesy & Copyright Shannon Rhodes, Photographer
Audio: Courtesy & ©
Text:     Shannon Rhodes, Edith Bowen Laboratory School, Utah State University
Additional Reading Links: Shannon Rhodes

Additional Reading:

Ash, Sidney. (August 2003). The Wolverine Petrified Forest. Utah Geological Survey.

Bartsch-Winkler, Susan, et al. (1990). Mineral Resources of the San Rafael Swell Wilderness Study Areas, including Muddy Creek, Crack Canyon, San Rafael Reef, Mexican Mountain, and Sids Mountain Wilderness Study Areas, Emery County, Utah. U.S. Geological Survey Bulletin 1752.

Bauman, Joe. (Nov. 26, 1997). Hot spot. Deseret News.

Gordon, Greg. (2003). Landscape of Desire. Logan, Utah: University Press of Colorado.

Hollenhorst, John. (May 26, 2014). Fossil-theft phenomenon has petrified forest visitors returning ‘keepsakes.’ KSL News.

Htun, Than. (March 6, 2020). P. Wood (Ingyin Kyauk): Poetry Written by the Earth. The Global New Light of Myanmar.

Mickle, D. G. et al. (1977). Uranium favorability of the San Rafael Swell Area, East-Central Utah.

Rawson, Peter and Aguirre-Uretta, M. (2009). Charles Darwin: Geologist in Argentina.

Van Wyhe, John. (2002). The Complete Work of Charles Darwin Online. (

Viney, Mike. (2015). The Anatomy of Arborescent Plant Life Through Time.

Utah at the Smithsonian

Utah at the Smithsonian: Click for a larger view of Diplodicus, Courtesy, Michael Brett Surman, Photographer
Michael Brett Surman, Photographer

Utah at the Smithsonian: Camarasaurus, Camarasaurus lentus (Marsh), Courtesy, Michael Brett Surman, PhotographerCamarasaurus
Camarasaurus lentus (Marsh)

Michael Brett Surman, Photographer

Utah at the Smithsonian: Smithsonian Butte, Public Domain, Courtesy National Scenic Byways Online, and Bureau of Land Management, John Smith, Photographer

Smithsonian Butte
Public Domain, Courtesy
National Scenic Byways Online and Bureau of Land Management.
John Smith, Photographer

Hi, I’m Holly Strand from the Quinney College of Natural Resources at Utah State University.

You don’t have to be in Utah to appreciate some of its treasures. Examples of Utah natural history can be found in museums around the globe. The last time I was in Washington DC, I explored the collections of the Smithsonian Museum of Natural History. There turned out to be a whole lot more Utah stuff than I ever imagined.

Many would consider dinosaurs to be our most illustrious museum export. Indeed a 90-foot long Utah diplodocus is the centerpiece of the museum’s Dinosaur Hall.

Not far away is an amazingly intact Camarasaurus from Utah’s Dinosaur National Monument. Its fossilized bones remained in position for over 150 million years. So beautifully and naturally preserved, it still rests on part of the sandstone block in which it was found.

Only a tiny fraction of the Museum’s collections are on display. The vast majority of its 126 million specimens are in drawers, vaults, and freezers. These items are meticulously cataloged and preserved and they serve as primary reference materials for researchers around the world. I found many 1000s of cataloged items for Utah plants, mammals and birds. Less abundant, there are still 100s of records representing specimens of our amphibians, reptiles and fish.

If you poke around in the collections databases you are sure to find something of interest. I found records of some 300 Utah plant specimens collected by Lester Frank Ward, a botanist who worked for John Wesley Powell on his western expeditions. Powell also contributed to the Smithsonian’s collection of flora and fauna. I found 8 bison skulls and one grass species, but there is probably more.

There is the skull and partial skeleton of a grizzly killed in Logan Canyon. Not Old Ephraim–his skull is here in Utah–but another one killed the year before.

In 1950, a meteorite struck a driveway just a few feet from a Box Elder County woman. A few years later, the meteorite was donated to the Smithsonian. But not before it was enhanced by local schoolchildren using crayons of various colors.

The museum’s mineral collection contains 1000s of Utah specimen, some with very strange names : I found Beaverite, Rabbitite Englishite, Coffinite, Psuedowavellite, Cristobalite, Alunite, Apatite and even Bieberite. As in Justin, I guess.

Anyway, you get the idea. The Smithsonian collections form the largest, most comprehensive natural history collection in the world. And Utah is a prime contributor of both collection items and the stories behind them.

By the way, not only are Utah things in the Smithsonian, but there are also Smithsonian things in Utah.

For example, the Henry Mountains in south central Utah were named after the first Secretary of the Smithsonian Institution Joseph Henry.

Another example is Smithsonite–or zinc carbonate–which was first identified by James Smithson in 1802. The very same Smithson left his fortune to the United States government, directing that it be used to create the Smithsonian Institution. The mineral Smithsonite has been found in Tooele and Washington Counties.

Lastly, there’s Smithsonian Butte. When the Powell Expedition traveled through the Zion area, geologist Edward Dutton named the Butte after the expedition’s most generous sponsor. Smithsonian Butte Road is a designated national backcountry byway, crossing over the Vermilion cliffs between Utah 9 and Utah 59.

For pictures, sources and links, go to

For Wild About Utah, I’m Holly Strand.


Images: Information and photos provided with the permission of the National Museum of Natural History, Smithsonian Institution, 10th and Constitution Ave. N.W., Washington, DC 20560-0193. (
Smithsonian Butte, Public Domain, Courtesy National Scenic Byways Online and Bureau of Land Management., John Smith, Photographer
Text: Holly Strand

Sources & Additional Reading

Panoramic Virtual Tour of the Smithsonian National Museum of Natural History (NMNH). Navigate or go directly to the Dinosaur Hall to see the diplodocus from Utah. (Fossils: Dinosaur 2)

Dinosaur page of the NMNH.

Research and Collections of the Smithsonian NMNH.

Access to Smithsonian NMNH Museum Collection Records databases

Smithsonite, Museum of Natural History, Smithsonian Institute,

Yesterday’s Camels

Yesterday’s camel
Courtesy Wikimedia,
Arthur Weasley, Artist
Licensed under
GNU Free Documentation License

Utah locations where
ancient camel bones
were discovered.
Courtesy BerkeleyMapper,
created by
Berkeley Natural History Museums,
UC Berkeley at

Map data ©2013Google,
INEGI Imagery, © 2013 Terra Metrics

Hyrum Museum
Courtesy Holly Strand, Photographer

Hi, I’m Holly Strand.

There’s a small, but very engaging museum underneath the public library in Hyrum UT. This museum showcases a number of artifacts reflecting the history, customs and environment of Cache Valley. When I first visited in 2009, a couple of odd items caught my eye. One was an enormous hairball that had formed in the stomach of a Cache Valley cow. Such hairballs are called bezoars, a Persian word meaning “antidote.” Centuries ago, bezoars were believed to be a universal antidote that could neutralize any poison.

The other odd item at the museum was a camel tooth. Now a cow hairball can seem geographically appropriate as Cache Valley has plenty of cows. But why would a camel tooth be in a museum about the history of Northern Utah?

Well it turns out that this particular tooth belonged to a native Utah camel species. It most likely came from we now call Yesterday’s camel (or Western camel) which lived over 10,000 years ago. This camel was twenty percent larger than a dromedary and had a longer, narrower head and thick muscled lips. Its footpad was soft and toes were splayed, approaching the foot structure of modern camels. We don’t really know whether or not Yesterday’s camel had a hump. Remains of this Pleistocene ancestor have been found throughout the American West and in a number of UT locations.

Further, I was surprised to learn that camels are a purely North American invention, first appearing some 40- 50 million years ago. At the peak of their North American career–during the Miocene–there were 13 genera of camels. Overall, at least 95 species in 36 genera have been described for this continent alone.

The earliest camel was no more than 2 feet high. After that we find camel legs and necks grew longer to allow browsing on trees and shrub tops. One particular species (Aepycamelus giraffinus ) stood 19 feet high. Essentially this camel had become America’s giraffe on what was then a Serengeti-like plain.

Other camels resembled gazelles, and still others looked more like the camelids of today.

4 million years ago, camelids first crossed the land bridge to Eurasia . Living in Eurasian deserts, they evolved into arid land specialists with a remarkable physiological capacity for water conservation.

Other North American camelids drifted south to colonize South America. They evolved into today’s llamas, guanacos, alpacas, and vicunas—all high altitude grazing specialists.

After a few waves of migration, camels suddenly vanished from their birthplace. In fact much of the North America’s megafauna suddenly vanished in the late Pleistocene. Perhaps due to human hunting, perhaps climate change. We may never know for sure.

But one thing is clear to me now–a camel tooth definitely has a place in a Utah history museum.

For more information and sources, and a link to the Hyrum Museum, go to

For Wild About Utah, I’m Holly Strand.


Image: Courtesy Wikimedia, Arthur Weasley, Photographer
          Courtesy & Copyright © Holly Strand, Photographer
          Courtesy BerkeleyMapper, created by Berkeley Natural History Museums,
          UC Berkeley at
          Map data ©2013Google,
          INEGI Imagery, © 2013 Terra Metrics
Text: Holly Strand

Sources & Additional Reading

Flannery, Tim. 2001. The Eternal Frontier: An Ecological History of North America and its Peoples, NY: Grove Press.

Honey, J. J. Harrison, D. Prothero, M. Stevens, 1998. Camelidae. In:
C. Janis, K. Scott, L Jacobs, (eds.), Evolution of Tertiary Mammals of North America, Vol. 1. Terrestrial carnivores, ungulates and ungulate-like mammals, Cambridge University Press, Cambridge, UKIrwin, Robert. 2010. Camel. London : Reaktion Books

San Diego Zoo Global. 2009. Extinct Western Camel, Camelops hesternus

Hyrum Museum
50 West Main Street
Hyrum, UT 84319

Fossil Formation

Fossilized fish
Mioplosus labracoides
Copyright 2013 Stokes Nature Center
Andrea Liberatore, Photographer

Fossilized fish
Copyright 2013 Stokes Nature Center
Andrea Liberatore, Photographer

Horn Corals from Logan Canyon
Copyright 2013 Stokes Nature Center
Andrea Liberatore, Photographer

Fossilized leaf
Copyright 2013 Stokes Nature Center
Andrea Liberatore, Photographer

Fossilized shells
Copyright 2013 Stokes Nature Center
Andrea Liberatore, Photographer

The most popular school program that the Stokes Nature Center offers is a geology lesson for second grade. I’m not sure what happens between second grade and adulthood to make our general perception of geology go from exciting to boring, but you would be amazed at how excited second graders get over rocks, and especially, over fossils.

Fossils are really quite rare – a very specific set of conditions have to be met in order to create one. Most living things decompose fairly rapidly upon death, leaving no trace of their existence behind. In order to create a fossil, this process of decomposition needs to be halted fairly rapidly, which typically means that the body is quickly covered by some kind of sediment – like sand, or soil or mud. For this reason, most fossils are found embedded in sedimentary rock. If pressure and moisture levels are just right, over the course of millions of years the organism’s molecules will slowly be replaced by minerals from the surrounding sediments – eventually turning bone into stone.

Only somewhere around one in a billion bones will make it through this process. From there the fossil has to remain intact and identifiable through eons of tectonic plate movement, earthquakes, and mountain uplift. Then, in order to be found it has to be located near enough to the earth’s surface, and in such a place where a human might come across it. Some geologists estimate that only 1 in 10,000 species that have ever lived have made it into the known fossil record, which makes me wonder what discoveries still await us.

Fortunately for us, prehistoric Utah was a place where fossilization happened with some regularity, as evidenced by places like Dinosaur National Monument and the Escalante Petrified Forest. Did you know that Utah has a state fossil? That distinction goes to the allosaurus, a predatory dinosaur that thrived during the Late Jurassic period. Numerous skeletons found in east-central Utah range in size from 10 – 40 feet in length, meaning this fearsome creature may have rivaled it’s more famous cousin Tyrannosaurus Rex for top predator status.

With such a rich fossil history, it’s not out of the question that you might stumble onto something truly amazing during a routine hike. Can you keep your find? Well, that depends on two things: the type of fossil, and whose land it was found on. On public lands in Utah, fossils of vertebrates cannot be collected, while fossils of invertebrates and plants can be. Private land owners have full rights to the fossils found on their property. With all fossils, it’s a great idea to report your find to the US Geological Survey so that your discovery can be documented for public or scientific research, display or education.

Fossil creation is an incredible phenomenon that has allowed us to glimpse the earth’s history in ways that would otherwise be completely hidden. Thanks to fossils, we can envision a prehistoric landscape filled with giant ferns, enormous dragonflies, long-necked allosauruses, and flying pterodactyls. Without the evidence in the fossil record, I doubt that even the most imaginative person among us could have envisioned such an amazing array of life.

For the Stokes Nature Center and Wild About Utah, this is Andrea Liberatore.


Photos: Courtesy & © Stokes Nature Center,
Text:    Andrea Liberatore, Stokes Nature Center,

Additional Reading:

State of Utah, Utah Geological Survey, Dinosaurs & Fossils (2011)

McCalla, Carole and Eldredge, Sandy (2009) What should you do if you find a fossil? Utah Geological Survey. Accessible online at:

Trefil, James (1996) 101 Things You Don’t Know About Science and Nobody Else Does Either. Houghton Mifflin Company: New York, NY,

Bryson, Bill (2003) A Short History of Nearly Everything. Broadway Books. New York, NY,