November 25 (1975, 1977, 1979, 1985, 2003) The Fog Arch ~
Pickering Bar

11/25/75   [...]

it is a sunny, breezy fall morning, oak leaves sailing about, and cedars dancing. further reading about the kuksu cult has shown that the very heart of the central california cultural/religious/mythological tradition is found among the patwin wintun and the valley maidu. among these peoples was found the greatest elaboration of theme. among their neighbors—the pomo, miwok, yuki, [costanoans]—the kuksu cult was rudimentary in comparison, the dances fewer, the emphasis different. the pomo accorded the highest position of all ceremonies to the kuksu, from which the secret society derived its name amongst the anthropologists who have studied it. yet in the geographical and spiritual heartland, among the patwin and the maidu, the hesi ceremony was considered the highest, most important; the kuksu dancer appeared in the hesi but the main figure was the moki.

among the maidu the clown—the pehiepe—was the fire-tender during the ceremonies in the earth-lodge. he parodied the dancers and priests, and according to jaime de angulo, the people of the village who attended the ceremonies, receiving from them a payment in beads if he could make them laugh.

~ mid-day a large pool of light on the floor, entering through my southern window from the low-angle sun of less than a month before solstice. i feel a kind of zen emptiness and quietness; the tree of my soul quivers in the autumn wind, and the stirring of my inner leaves makes my hair try to stand on end, a kind of thrilling echo of what goes on ‘outside.’”


11/25/77 morning, moody ridge. returned last night [...] it had been cloudy since the Big Storm of last weekend that dropped over five inches of rain on moody ridge; yesterday the sky cleared, late in the day; and today, sunny and clear, with just a few lacy cirrus to the south and east. [...]


11/25/79 oak leaves have fallen, changes, changes…

[...]

such a pretty morning. fog gilded in the rays of the rising sun, fog like a huge sinuous rainbow sagging into the slot of the north fork canyon. and the pinnacles are watching. lover's leap's awake. lovers' lips awake.

[...]

on wednesday I worked a bit on burn piles, neil was over, hauling firewood, [...]

i am improving my cabin. maybe add a bathroom, stove room.

[Jon's] backhoe is still parked up in the meadow. much brush remains, but a central corridor has been cleared. it will be lovely but i am still in shock at the huge muddy expanse, and all the slaughter of trees, bushes, the leveling by flames of wood rot palaces.”


November 25, 1985

Today I worked at the McClungs' and to my great satisfaction was able to drive all the way into the meadow for the first time in more than two weeks. It had been foggy with light rain for most of the day, but as I returned I beheld a splendid panorama of sun and rock and fog and forest in the canyon. The spectacle continues, though it grows late and the sun's force wanes, so briefly brought to bear upon this minuscule corner of our tiny world.

My thoughts had turned, as I perched on the couch, gazing, to my capacity for independent observation and thought. Observation is nothing without the thought behind it; another subject.

Instances of my own ability in this way came to mind (there are numerous such instances, since my nature keeps me questing, questing), such as becoming attuned to the fire scars on the uphill sides of trees, where the (often) upslope winds that fan the flames onward actually have a cooling effect upon objects in their paths; plus accumulation of fuel is more likely on the uphill side of a tree, because the (usual) decrease in slope angle in such locations, plus the capacity of the tree trunk itself to arrest the downslope movement of fallen branches, etc., can create a fuel excess, and a hotter, more scarring fire, in such locations.

But, fuel excesses aside, the mere cooling effect of that phenomenally hot wind protects in some measure the seemingly more exposed, downslope sides of tree trunks. The upslope, and therefore lee side of the trunks is deprived of this cooling.

Or is this enough? I do not think so. Turbulence is created in wind flow patterns when an obstacle is diverting flow: pressure spindles of hot and cold and warm and cool air are entrained together: and when they reach the tree trunk—and when they pass it—low pressure is created on the lee of the trunk. Strong low pressure is created, and flames fed by fuel downslope (another tree, or some bushes, for example) are split asunder by the trunk and become entrained in paths of least resistance that lash back at the trunk from each side: and it is primarily for this reason, that pressure drops on the lee side of tree trunks, and lashing flames are entrained, held close to the tree, that such damaging burns occur on those sides, the lee, uphill sides of trees.

And when a monster Kellogg's Black Oak is engulfed in the flames, the rough texture of its age-old bark is erased, burned away; thirty years later, all one sees is that the bark on the uphill sides of these oaks is smoother and somewhat lighter in tone.

There's certainly more to be said about the uphill, lee sides of trees in fires. But the other instance that came to mind is the matter of fog and fault zones. I have independently observed this phenomenon.

Across the canyon from here, the main spur of Giant Gap Ridge thrusts to the north into the North Fork canyon. About five hundred feet below the rim, the spur's ridge line levels briefly, then resumes its two thousand foot plunge into Giant Gap. That leveling is the trace of an ancient fault running transverse to the spur-axis. It is mapped as ending a short distance to the east at another, larger fault, bounding the New Melones serpentine to the eat, and the Cape Horn formation to the west. Along both faults, linear groves of Black oaks have held sway for millennia. In the serpentine, the vegetation shifts abruptly to digger pine and canyon live oak, with heavy chaparral formation.

In the Cape Horn formation, vegetative cover is largely a function of slope angle and aspect, with canyon live oaks holding the steeps, and dense coniferous forest, the flats.

But the faults bring another variable into play, the shattering of rock and consequent increase in soil depth due to faster weathering. The Black oaks on both faults are exploiting this unique soil, and benefit as well from the enhanced ground water profile existing in zones of shattered rock like these. Which brings me to the fog syndrome: this little, transverse fault, with its patron grove of ancient oaks, can often be seen in stormy, or in the period of clearing after stormy weather, to have a cute little arch of fog hovering over it. Sometimes, the only shred of fog to be seen will be perched there; at other times, the whole canyon will be an enormous seething cauldron of fog, a bizarre amphitheater within which unspeakable dramas unfold, and still this little arch hangs there, holding its station faithfully against fearful odds, against massive air mixing, turbulence, thermals and anti-thermals…

Why?

Why do fog and black oaks, arches and arches, like this little fault? For millennia they've liked it.
   
I think they've liked it for partly the same, and partly different reasons. First, there is a mat of soil masking the fault itself. Rock that was shattered 150 million years ago has developed a substantial soil profile and the black oaks are exploiting it. The mat of soil and vegetation masking the fault is a moist zone, and winds that blow through it are relatively wetted compared to winds sweeping the adjacent live oak forest. Winds… Winds often blow up the canyon and they often blow down the canyon.

Upcanyon winds occur every day in fair weather and also during storms (southwest wind). They are katabatic winds, upslope winds, daytime winds. At night flow reverses, becomes downslope, anabatic, as were Xenophon and his men, wending their way down from the mountains to the sea.

The spur obstructs these winds and compressed,  they are accelerated across its crest, creating low pressure below, especially to the lee: thus air is entrained from below and drawn as if  into a whirlpool, towards the crest: and when this warmer moister air is cooled by rising, it can cross the dew point, and the water in the air condenses into tiny droplets: fog.

The leveling of the ridge at the fault may serve to focus the entrainment of air across the crest even further: this an arch of fog, for air entrained to this focal point on the spur would be accelerated the most, create the largest pressure drop, and consequently be able to pull, or reach deeper (into warmer, moister regions) than other places on the spur crest.

Since the spur lies transversely to the canyon, but the little fault lies parallel to the canyon, air movement parallels the little fault (typically): therefore, entrainment of air towards the focal point will be selectively enhanced in the direction parallel to the little fault, and since the focal point is therefore always downwind from the liner grove of oaks on the fault, this relatively moist air is selectively entrained across the spur.

[Russell Towle's journal]


Pickering Bar Trail
[North Fork Trails blogpost, November 25, 2003:
http://northforktrails.blogspot.com/2003/11/pickering-bar-trail.html ]
Yesterday I joined Ron Gould for a hike on the Pickering Bar Trail, near Gold Run. From the Gold Run exit on I-80, south side, we drove west on Magra Road and then almost immediately turned south on Garrett Road, which parallels the Diggings for a mile and some before reaching the rim of the North Fork Canyon. There it bears east and a large BLM gate blocks further travel, except by foot or OHV.

There are no signs indicating that this is public (BLM) land, nor that a trail to the river exists nearby. In fact, on the last stretch of the road before it bends east to the gate, one has the distinct sense that one is trespassing, for the road also gives access to private property, and one sign boldly proclaims "No River Access."

I had never obtained GPS coordinates for the Pickering Bar Trail. Until a few years ago, one could drive to the trailhead, but now the gate must stand for the head of the trail, so I switched my little Garmin unit on right there, and, in the open, manzanita-cloaked terrain, soon obtained excellent satellite coverage. Off we went, loppers in hand.

It was a cool but sunny morning, just a few wisps of cirrus cloud here and there, and, with the sun angle so low now, near the solstice, much of the great canyon was in shadow, and was a vast blue depth beside us, only half-seen through a screen of trees and bushes. The road is ancient, in California terms, already existing at the time of the 1866 General Land Office map, when the section lines were laid out. It is marked as "Road to the Mines" on that map, and is shown terminating at the Secret World, at the head of Indiana Ravine, which is the very site of the discovery of gold at Gold Run. This is where the road ends to this day. It is becoming badly blocked up with fallen Knobcone Pines, which seeded in thickly after the 1960 wildfire, and now die in their dozens and topple over in windstorms. The storms hit hard along the rim of the North Fork canyon.

There have been many fires in this area, many fires raging up the canyon wall, as evidenced by the gigantic expanses of manzanita (all the White Manzanita, Arctostaphylos viscida), the preponderance of Sugar Pine over Ponderosa Pine, and the high incidence of Knobcone Pine. The road winds in and out of various ravines all tributary to Sheldon Ravine, and in a quarter-mile one passes a road left into the Diggings, close, but screened from view by manzanita all along the way. After another turn in and out of a ravine, the road levels and a bad old bunch of hefty Knobcones bars the way. The OHV users have cut a side trail around the fallen trees, and in another fifty yards one reaches the trailhead, a large sunny flat becoming choked with a million young manzanita bushes, seeded after semi-recent bulldozer activity, by the looks of things. The trail leads away to the south, past two middling large pines, and over the first several hundred yards, follows a bulldozed fire trail right down the spine of a ridge. This would seem to have obliterated the original trail, which may have followed a gentler line, winding back and forth across the slope, rather than straight down the ridge-crest.

The Pickering Bar Trail is not depicted on the USGS 7.5 minute Dutch Flat quadrangle. If you have that map, note the words "Sheldon Ravine," on the north side of the river, and west of Pickering Bar itself. The old trailhead on the road is near the southern end of the 3000-foot contour, and the trail drops away south right through the word "Sheldon."

At about 2750' elevation, just after leaving all traces of the bulldozed fire trail behind and entering upon the Pickering Bar Trail proper, one reaches a rocky outcrop of chert, laced with quartz veins. A truly marvelous view of the canyon is had from here. One might well hike the Pickering Bar Trail just to reach this one viewpoint. It might be called Chert Point. Quartz crystals sparkle in the sun. One can see from Iowa Hill on the west to and through Giant Gap on the east, and beyond to Sawtooth Ridge, and Monumental Ridge, with its snow.

Continuing down the very steep trail, at about the 2640' elevation, a faint trail leads away west. Others like it are in the area, but are blocked by brush; this side trail is open, and in a short distance one reaches Sheldon Ravine, a narrow slot cut in parallel to the strike of the vaguely slaty bedrock, which here I take to be part of the metasedimentary portion of the Calaveras Complex, a Paleozoic "terrane" accreted to North American long ago. The strata are near-vertical and strike south. A faint game trail which might just be a human trail continues west across the ravine; we did not explore it.

Sheldon Ravine might have had its own "tailings claims" once upon a time, with sluice boxes set to extract gold which escaped the sluice boxes of the hydraulic mines in the Diggings, above. We saw tailings lodged in the bed of the creek (now dry), which the signature rounded white quartz cobbles which betray their origin in the Eocene-age river gravels of the Ancestral Yuba, which flowed north here, from Iowa Hill to the south, through Gold Run to Dutch Flat, and then on to Little York and You Bet, etc. etc.

The trail is relentlessly steep and often hemmed in by heavy brush. We lopped hundreds and hundreds of branches. Around the 1800-foot contour, we saw still another faint trail leading away into Sheldon Ravine, and explored a little ways. There had been many such trails along the way, just barely too well-defined to pass as game trails. Ron then spotted a mining ditch below us, and he made for it directly, while I returned to the main trail to see if it cut the ditch-line. I had no memory of a ditch this high above the river. But, there it was, except, it seemed the ditch came from Sheldon Ravine and ended on the spine of the ridge, where it had been turned into some minor penstock of iron or canvas; a shallow gully went straight on down, and I recalled the last time I had hiked the trail, I had interpreted this shallow gully as the trace of a lumber slide, similar to the one over on Diving Board Ridge, across Indiana Ravine to the east.

`

The ditch was almost impossible to discern, from the trail itself, partly because rather large bushes nearly covered it. I forced a way through this snarl of Buckbrush and Toyon and Manzanita with my loppers and on the far side found a lovely broad terrace, winding away through the brushy forest, and mostly open and clear. It followed a much steeper line than most ditches, but was, unequivocally, a ditch. It had a bit of dry-laid stone wall bolstering it in many places, often all but hidden within masses of moss. I caught up with Ron and we slowly worked our way in to Sheldon Ravine. The last fifty yards were really beautiful; the ditch was formed a broad grassy terrace atop a cliff perhaps a hundred feet high, where quite a nice waterfall will form later in the winter. There was a faint suggestion of a trail continuing west across the ravine, but we did not explore it.

We returned to the main trail slowly, putting the finishing touches on our lopping job, and soon reached the place where the main trail bends sharply left, really more north than east, about 300 feet above the river, which hits the 1440' contour at Pickering Bar. Various trails lead away to the right, southwest, let us say, as one descends the main trail. I have followed a couple of these. One leads to the Flat of the Chinese Coin, as described by Mike Case recently here. Along this part of the trail, one suddenly begins to see the California Nutmeg, a strange conifer in the Yew family, with brash sharp needles about two inches long, and single seeds which resemble huge green olives. It might easily be mistaken for a fir.

The main trail becomes narrower and fainter and finally takes a drastic plunge right down to the river, where, just as we had seen high above in Sheldon Ravine, the river runs parallel to the strike of the bedrock. Some rather fantastically eroded sections of bedrock flank the river here, while across the river rises Pickering Bar, a large glacial outwash terrace. We were right across the river from the "B" in the words "Pickering Bar" on the Dutch Flat quadrangle.


After a lunch break, we lost our precious sun, but explored a bit before hitting the trail for the long slog out. Goodness gracious, that is a steep trail. It is probably not much more than a mile in length, from the old trailhead down to the river, but seems longer, and however long or short it may be, it is strenuous.

Reaching the top, we followed the old road for a ways, and then struck north into the Diggings, through one of the precious few gaps in the wall of manzanita. As soon as we entered the sacred precincts we heard voices, and after some wandering, caught glimpses of people over on the Bluffs, apparently hanging from ropes, and having a wonderful time, doing what, we had no idea.

We slowly approached. I wanted to show Ron the place where the last big log of petrified wood had been, before being stolen by a mining claimant, and as it happened, the rope-swinging cliff-climbing party had left their packs there. They were over on a sort of Macchu-Picchu-looking spire of sediments, near a secret trail up to Garrett Road. Ron and I turned to leave, and just then the distant cliff dwellers set up an even louder hue and cry, and we began to hear my name, "Russell Towle," and that hardly seemed likely. So we stopped and finally I shouted, "Who are you?" and it turned out to be my old friend Alex Henderson, now a fireman in Sacramento but for many years a resident of Dutch Flat. He had brought his children and a niece and nephew to the Diggings to explore and mess around on crumbling epic clifflets using ropes.

After a time they scrambled down into the Diggings and hiked over to us, and we had a pleasant chat before returning to the road and the trucks. Alex et. al. had actually ventured a little ways down the Pickering trail, earlier, and saw they were on my track by the lopped branches, but had been scared from following further when the trail steepened so badly, below Chert Point. So they entered the Diggings and swung around on ropes.

It had been a wonderfully sunny day, perfect hiking weather, great views, the river itself as beautiful as always—I got some nice photos of the sunny bluffs of Pickering Bar, reflected in the quiet low water of Fall. Water Ouzels and Canyon Wrens were much in evidence, down there.


And such was a great day in the great canyon. I especially liked finding the old mining ditch, now just a perfect terrace for resting and dreaming and taking the sun, and soon to be adorned with its own high waterfall.



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