Rock Out

The Wedgwood Rock; photo by Dennis Bratland via Wikimedia Commons (CC BY-SA 4.0)

Giant ‘wandering’ rocks deposited by glaciers are fascinating — and fun to climb on

By Annie Fanning

Like an old-growth tree, a magnificent rock has a presence about it — a spirit, if you will. You don’t have to understand geology to commune with a great rock — or scramble up it and stand victorious on top — but knowing a little about the forces that created and shaped such rocks can turn a big boulder into a reallife natural history experience.

Wandering rocks When the glaciers advanced into the Puget Sound region 2 million years ago, the major features of our Northwest landscape — the volcanoes, mountain ranges, rivers and basins — already existed. The glaciers, colossal sheets of ice on a continental scale, scraped and sculpted the terrain with cycles of freezing and flooding.

As the ice advanced, sheering cliffs and cutting ravines, the glaciers picked up hunks of rock and carried them along. When the ice melted, these rocks were left miles away from their place of origin.

Rocks that have been transported by glaciers are called erratics because they have landed somewhere far from their natural homes.

continued from page 37 upon close inspection, are unlike any of the other rocks in the area. They often contain veins of minerals and other unusual surprises, such as fossils.

Technically, a pebble transported a great distance by glacial activity can also be considered an erratic, but these are harder to notice. And people sometimes refer to large landscape rocks as “urban erratics,” which is fun but not really correct, as glaciers had nothing to do with their turning up in your garden.

Geologists, natural historians and friends of rocks (and kids who like to climb stuff!) prize naturally placed erratics because these unusual rocks provide important clues to the geology of our region — and plenty of fun.

Climbing boulders Like climbing trees, scrambling atop big rocks is one of those genuine childhood pleasures that these days, with our nature deficiency, we have to schedule into the family program..

It’s okay to encourage kids to climb rocks! And it’s cool for grown-ups to climb rocks, too. For a quick afternoon pickme-up in any season, there’s nothing like scaling a boulder to elevate energy and make you want to woot! with joy.

Climbing tips: Use your best judgment. Some erratics are more scramblefriendly than others. Some are just too big to climb safely without proper climbing equipment; others are in balance with a fragile ecology, so be mindful of their lichen, moss and ferns. Some have been posted with signs prohibiting climbing. Even if you can’t climb, whenever possible, touch the rock, lean against it, smell it, measure it against your body. Take time to inspect it closely for fossils and minerals as well as interesting mosses and lichens. Introduce yourself to the rock. Make friends.

Now let’s go climb some rocks!

Fantastic Erratic on Cougar Mountain; photo by Peter Stevens via Wikimedia Commons (CC by 2.0)

Cougar Mountain’s Fantastic Erratic, Issaquah

Wearing a gorgeous shag of licorice fern, the Fantastic Erratic watches over the Talus Open Space adjacent to Cougar Mountain Regional Wildland Park in Issaquah.

For a quick visit to this majestic wonder, park at the Bear Ridge trailhead off SR 900 and take the Bear Ridge Trail uphill about a mile. For a longer hike, you can come down on the Shangri La Trail. Deposited on this hillside by a northern glacier, this erratic is metamorphic, created under the Earth’s surface by intense pressure and heat. In some of its jagged cracks you might notice orange staining, which is from iron-rich water percolating through the rock. The ferns must lust for rust because they are really digging into this erratic!

Getting there: From Interstate 90, take exit 15 and drive south on 17th Avenue Northwest, which becomes RentonIssaquah Road Southeast, also called SR 900. Just past Talus Entrance Road, look for the small parking area at the Bear Ridge trailhead. Note that Bear Ridge Trail connects with King County’s Cougar Mountain Regional Wildland Park trail system.

Follow the trail uphill for about a mile. It may seem longer, but it is not. Bring chocolate.

If you go: Drive back through Issaquah if you’ve worked up an appetite. Pick up kid-friendly Indian takeout at popular Bukhara (131 Front St. N.). For lighter fare or hot chocolate, try Issaquah Coffee Company (317 N.W. Gilman, No. 47).

The Wedgwood Rock, Seattle

This incredible erratic holds court in an informal pocket park at the intersection of Northeast 72nd Street and 28th Avenue Northeast in Seattle’s Wedgwood neighborhood.

According to Maria Dolan and Kathryn True’s excellent guide “Nature in the City: Seattle,” the Wedgwood Rock was formed 163 million years ago, but deposited by the Puget lobe ice sometime between 15,500 and 17,000 years ago. And according to historian Coll Thrush in his book “Native Seattle: Histories From the Crossing-Over Place,” the Wedgwood Rock was once a meeting place for the native peoples of the region.

Approximately 20 feet tall, 75 feet around and ringed with conifers, this marvel should be admired but not climbed upon, as there is a $100 city fine for those who try to scale it.

Unlike some other erratics thick with ferns and moss, the Wedgwood Rock’s moss is thin and patchy. The serpentinized greenstone that makes up this rock is low in plant nutrients and high in toxic metals. (So, don’t lick this erratic!)

For the most fun, park at Dahl Playfield and walk neighboring streets uphill to the erratic. In addition to parking, the Dahl Playfield has rocks aplenty to climb on in the play area, including a stony art installation by John Hoge called “Boulder Wash.”

Getting there: Dahl Playfield is located at 7700 25th Ave. N.E., in Seattle. To walk to the erratic, exit the playfield at 26th Avenue Northeast and carefully cross Northeast 75th Street. Continue on 26th until you reach Northeast 72nd and follow it uphill to the erratic at 28th Avenue Northeast. ►

continued from page 39 If you go: Bring your wheels. Dahl Playfield has plenty of paths to scoot along, plus a skate dot.

For some of the best baked goods in the city, head over the hill to Grateful Bread at 7001 35th Ave. N.E.

Martha Lake Airport Park boulder, Lynnwood

Snohomish County Parks gets major props for preserving the erratic at Martha Lake Airport Park by cleaning it of graffiti and honoring it with an informational sign. Covered with spray paint, erratics can tell us very little. When we can see the stone and examine its natural color and texture, we can guess at its history.

About 18 feet tall, this lovely rock is probably greenschist, a mineral-rich basalt that has been chemically changed by heat and pressure long ago under the sea floor. This type of erratic is common in lowlands of the Puget Sound area.

Getting there: Drive to Martha Lake Airport Park, located at 200 146th St. S.W., Lynnwood. You’ll find the rock tucked behind the picnic shelter.

If you go: Bring your wheels! This park has a skateboard ramp and scooter-worthy paths. After your rock appreciation, chow on super nachos and quesadillas at Casa Guerrero at 402 164th St. S.W., in Lynnwood.

Upper Leschi Park erratic, Seattle

In the natural area on the slope above Seattle’s Leschi Park tennis courts, you will find this gorgeous trailside erratic. special erratic was made by the compression of layers of sand or silt. As a result, the ancient submarine rock is a little more brittle than most, so be gentle with your affections.

Unfortunately, a few selfish rockhounds have been trying to collect fossils here. The damage they’ve made with their hammers is irreparable. Leave no trace of your visit. Take only pictures.

Getting there: Leschi Park, at 201 Lakeside Ave. S., is located south of Madrona Beach on the shores of Lake Washington. You can find street parking along Lake Washington Boulevard and take the old cable car bridge to East Yesler Way. Follow the trail uphill into upper Leschi Park’s natural area.

If you go: Bring a picnic or grab a delimade sandwich at the family-owned Leschi Market at 103 Lakeside Ave.

Or, climb the hill to 34th Avenue in nearby Madrona and find an array of ice cream, cake and espresso opportunities, including the original Cupcake Royale (1101 34th Ave.) and Molly Moon’s Homemade Ice Cream (1408 34th Ave).

Big Rock of Duvall

Nestled between two giant redwoods in a pocket park southwest of Duvall’s Main Street Safeway lies this enormous, historically significant erratic.

Already an ancient wonder of the Snoqualmie River Valley long before the town of Duvall was established in 1913, so-called “Big Rock” has a road, a park and several businesses named after it. The sequoia trees that keep it company are probably more than 100 years old themselves. Big Rock is a gneiss (pronounced “nice”): It’s a rock sandwich made up of different rocks and minerals all smooshed together, often in visible bands or stripes. Look for bands of white quartz in Big Rock and admire its patterns of lichens and moss.

Getting there: Located between Monroe to the north and Carnation to the south, Duvall sits on State Route 203, which doubles as Duvall’s Main Street. South of historic Main Street you will find Duvall’s Safeway at 14020 Main St. The erratic is located southwest of the parking lot.

If you go: Enjoy the pleasures of a small-town Main Street in Duvall and have a treat at Grateful Bread Bakery (15602 Main St. N.E.).

Big Rock of Duvall; photo by Dennis Bratland via Wikimedia Commons (CC BY-SA 4.0)

Two excellent erratics, big and small, in Des Moines

There are two erratics to visit in Des Moines: an enormous one at Highline College and a pretty, petite one at Des Moines Beach Park.

Dominating a landscaped bed of rosemary and fountain grass in front of the Higher Education Center, Highline College’s monster erratic is so heavy (more than 2 tons) that it held its ground against two Caterpillar bulldozers

during the building’s construction!

Predominately salt-and-pepper granite, this easily climbable rock has been polished smooth by grit under the glacial ice. With its southern exposure, this erratic grows warm in the sun, making it a perfect spot for students to lounge and catch a few rays.

Crouching like a stone lion watching the tide, the second erratic sits on the Des Moines waterfront. Only 4 feet high, this erratic looks nothing like the other rocks north of the marina at Des Moines Beach Park.

Look closely: This noble glacial rock is flecked with sparkles of mica and streaked with veins of smoky quartz. Getting there: Highline College, at 2400 S. 240th St., in Des Moines, is a few minutes from Interstate 5. The erratic is adjacent to the south parking lot, in front of the Higher Education Center. To avoid dealing with parking permits, plan to visit on a weekend or a holiday.

Des Moines Beach Park, at 22030 Cliff Ave. S., is a short drive from Highline College. Park near the historic Des Moines Beach Park Event Center. You will find the erratic on the beach, north of the marina’s jetty.

If you go: You’ll find some good eats on Marine View Drive. Try Des Moines Dog House (22302 Marine View Dr. S.) and Auntie Irene’s for ice cream and other treats (22504 Marine View Dr. S.).

Erratic on the Des Moines waterfront; photo by Dennis Bratland via Wikimedia Commons (CC BY-SA 4.0)

Editor’s note: This article was originally published a number of years ago, but the big rocks haven’t changed a bit since then. ■ Annie Fanning is a mother of two brilliant daughters, a Seattle Tree Ambassador and a flower-throwing anarchist.

COMFORT & JOY