The Best Thing You’ll Read About Bark Today (If You Don’t Read Anything Else about Bark)

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This post is about bark.

I know what you’re thinking. “Bark—an enthralling topic!” I couldn’t agree more, but bark is often overlooked and ignored by most people. Yet bark records many events in a tree’s history.

Thin and smooth barked trees like quaking aspen (Populus tremuloides) are especially good at recording animal sign. Aspen is the most widely distributed native tree in North America. Its bark becomes thick and furrowed only on old trees, and usually only near the ground. Most of the time aspen bark is smooth, colored white to gray (even greenish on young trees) with dark chevrons where self-pruned branches fell to the ground.

Since aspen bark is thin-skinned, it’s easily scarred. Along hiking trails, you’ll commonly find names and initials carved into it. (Don’t do this. No one cares if you were there with your “true love,” who you probably dumped the week after, and it opens the tree to possible infection.) Aspen bark records more than human impulses though. In bear country, you can often find evidence of bears climbing the trees.

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Black bears have five toes each equipped with claws superbly designed for climbing. Scars on trees from climbing bears usually come in sets of five.

Black bears are particularly adept at climbing trees. Their strength and relatively short, sharply curved claws help them gain purchase even on smooth barked trees like aspen. If I’m in an area where black bears live, I almost always look for bear claw marks on aspen. In the Stehekin Valley, bear claw marks are easily seen on aspen along the Stehekin River Trail and Agnes Gorge Trail.

The claw marks represent a moment in time. Under what circumstances were they made? Was a bear startled by a person? Another bear? Was it simply playing or exploring? Black bears are omnivorous, but I have read no records or seen any signs of them eating any part of aspen trees, so they probably weren’t climbing the tree for food. In the eastern U.S. though, black bears often climb another smooth barked tree, American beech (Fagus grandifolia), to feast on beechnuts.

The next time you find an aspen, take a closer look at its bark. Bark isn’t as static as its outward appearance suggests. You might find a story there.

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Short Ride Up Stehekin Valley

October has been a wet month here in Stehekin. So far, seven inches of rain have been recorded. Today brought a break in the weather though. When I saw clear skies this morning, I ate a quick breakfast and hopped on my bike for a ride up the Stehekin Valley Road through Lake Chelan National Recreation Area. I wanted to casually revisit different habitats along the way while enjoying bold fall colors.

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Snow-capped mountains over Lake Chelan

For the first mile the road hugs Lake Chelan’s rocky shoreline. The shallow areas near the head of the lake are popular with waterfowl right now. With the birds and the view of the mountains, I could’ve spent the whole morning near the dock at the Purple Point Campground. But, I probably would’ve chosen a different spot to linger, since I don’t necessarily enjoy the smell of rotting kokanee (land-locked sockeye salmon).

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Many dead and dying kokanee salmon are flushed from Stehekin River into Lake Chelan. This one, and many others, accumulated at the dock for Purple Point Campground.

 

The road quickly leaves the lake and roughly parallels Stehekin River for the next 12 miles.

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Stehekin River rises and falls considerably from peak runoff in late spring to its low point in late summer. It’s come up at least a foot since rain returned to the area, but is still several feet below its seasonal high.

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Stehekin River

The river is fed by several tributaries. Rainbow Creek is probably the most well known. From a hanging valley, it pours over 300 foot high Rainbow Falls onto an alluvial fan.

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Many small tributaries of Stehekin River form alluvial fans where they encounter the valley bottom. Rainbow Falls is tucked back behind the trees at upper center.

Alluvial fans on the side of the valley are typically dry, fire prone habitats. Around Rainbow Falls, fire is managed through controlled burns, which keeps the understory clear and trees well spaced. Usually, only plants with very high tolerances for hot, dry soils live here. The soils on the alluvial fans aren’t particularly rich either, which is one reason my garden, located on the toe of one these fans, sucked this year.

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Several species of manzanita (Arctostaphylos sp.), also called kinnikinnik or bearberry, inhabit the area, especially in dry sites. Black bears feed on the berries, but I find them mealy and almost flavorless.

 

Shortly after Rainbow Falls, the pavement ends next to a talus slope….

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…and the road weaves its way on top of more alluvial fans and down to the floodplain.

Areas that are prone to flooding or have wet soils have a far higher proportion of deciduous trees, like black cottonwood and red alder, than the adjacent uplands.

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Along the whole route, I stopped frequently just to enjoy the scenery.

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At the boundary between Lake Chelan National Recreation Area and North Cascade National Park, the river flows through a narrow valley where wet and dry microhabitats can exist within feet of one another. Plant life here is fairly diverse. Most of North Cascades tree species are found growing in the upper Stehekin watershed, and it’s a good place for animals too. Often I find fresh bear scat and tracks on the roads and trails.

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Tracks from a black bear that had walked on the road not long before I passed through.

Near the end of the road, I was forced to cross the river on this rickety down tree.

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Just kidding. I crossed on a sturdy bridge.

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But, within a few more minutes was met with an ominous sign.

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Impassible Beyond Here

Habitats along Stehekin River are subject to change, especially when the river floods. Just beyond the sign, the road is washed away.

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Road’s End: A 500 year flood washed away large sections of the Stehekin Road in 2003.

Here, I turned back to enjoy the mostly downhill ride home. Of course, fall colors and scenery kept distracting me, so I didn’t ride too fast, just enough to remain comfortably warm.