Finding fossils in Fossil, Oregon

About two hours from Bend, past the lava beds that produce world famous thundereggs, past the would-be utopia turned ghost town of the Rajneeshees, and almost directly north of the Painted Hills, there is a town called Fossil. It has a high school with a graduating class size of five.

The hill behind that school’s football/baseball field is full of 32 million year old fossils. You don’t need to be a paleontologist to find them!

The town of Fossil sits on the edge of what once was a shallow lake during the Oligocene epoch. A milder, wetter climate fostered lush growth. Many of the leaves that dropped became well preserved in the silt of the lake bed.

The site at Fossil High contains almost entirely plant fossils of the Bridge Creek flora. Metasequoia – a type of redwood – are most common, though birch, poplar, elm, and even hydrangea can be found.

Digging is discouraged at the site and you can do quite well picking through the “float” found on the surface of the hillside. Often, you can find nice fragments in that float material. More dramatic specimens, though, can be found by carefully splitting rocks.

Most rocks are sandstone or siltstone and split with a well placed strike. A small chisel or blunt pocketknife paired with a hammer does the trick, but hitting a stone against a bigger stone can work too. Look for lines on the side of a rock or rocks that already exhibit flaking in layers for best results.

A successful split will usually give you two matching fossils!

Fossils were discovered on the hillside in 1949 and are still there thanks to decades of considerate visitors. The Oregon Paleo Lands Center asks that you don’t break too many rocks and only take home 3-4 examples per person each visit.

Unlike the hulking dinosaur bones you’ve seen in museums, most plant fossils at this location are only traces of the plants that created them. Even the petrified wood found in other parts of Oregon is different. Petrified wood of the sort that still shows rings and takes a polish typically underwent permineralization – that is, the wood was replaced over time with mineral deposits. The silt of the lake bed at the Fossil High site created fossils in a different way – usually through compression.

In some cases, all that’s left here is an impression of the leaf with no plant material left behind. These impressions look like a cast was made of the plant material and can be hard to spot if not careful (harder still to photograph).

Many fossils formed by compression at this location may leave an impression but also still have a carbonaceous film. This carbon-rich material can sometimes leave shiny black streaks resembling coal when the plant matter wasn’t preserved. What we’re mainly looking for, though, are pieces with intact leaves.

The film that shows leaf patterns is really thin. It’s easy to chip right through it, so it’s best to take care with the flaky layers of rock that you handle. Complete leaves are hard to find here, but species identification is still possible from fragments.

Metasequoias like the the above are the most common species at Fossil High. These ancient redwoods dropped their needles seasonally and left a lot to find in the silt. They were thought to be extinct until a stand was discovered in China in 1944. Now, they’re a popular ornamental that you can buy at a garden store.

The last of the pictures above strongly shows a combination of an impression with the carbonaceous film remaining.

One of the more unusual pieces I’ve found at Fossil is this piece of wood. Cracked accidentally, the only face where the wood grain is visible is along the revealed surface! Unlike permineralized petrified wood, the wood structure is not apparent throughout the body of the rock – only that thin carbonaceous film. (There’s a chance this isn’t wood at all, but just an interesting pattern.)

Another somewhat exotic find is this hydrangea. You can see how delicate and thin the fossil layer is in the siltstone here. But what remains shows a fantastic level of detail! There appears to be remnants of the cuticle and even some plant matter at center.

Scientists (paleobotanists) have actually been able to conduct microscopy on the cuticle of similar fossils millions of years old. If this sort of thing interests you, the textbook Paleobotany by Taylor has great pictures and accessible descriptions.

Flowers and delicate plant structures don’t survive into fossil formation in most cases, so it’s special to find items like this – even as fragments. That said, organelles and chloroplasts have been found at Succor Creek in Oregon!

You’ll want to spend a full morning or afternoon poking around out at Fossil, so don’t pack too much into your trip out there. Adding a hike at the nearby Clarno unit of the John Day National Monument (above) can make for a full day trip from Bend. More fossils can be seen at the palisades there, but those are on federally protected land.

The scenery in this part of Oregon and the drive out there is breathtaking.

More information

Learn more about the science and history of the Fossil area at the Oregon Paleo Lands Center also in Fossil.

Read an in-depth analysis of the Fossil site from the journal Oregon Geology (PDF).

Visit Fossil, Oregon

Fossil is far from just about everything. Bring plenty of water and snacks and keep your vehicle topped off. There is a small general store and pizza in town, but that’s about it.

Dogs are discouraged on the high school’s hillside. Remember, kids and adults pick through the rocks here, so be considerate and take the potty breaks elsewhere. I was the only person there all day on my last visit so felt comfortable letting Cooper hang out with me.

There is a donation box at the entrance to the site and $5 per person is recommended. Donations help keep the site maintained and support the Oregon Paleo Lands Center.

It is also asked that you don’t take more than 3-4 specimens per person each trip. That’s a good excuse to plan another trip back!

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