So I gave Ron a call, and managed to meet him in Colfax around nine in the morning, the uncluttered blue of the early morning sky giving some way to an isolated shield of altocumulus clouds, with a few fair-weather cumulus popping up below, showing surprisingly strong vertical development for that early in the day. We set off on the road to Mineral Bar and Iowa Hill, with all its intricate curves, and fantastic views of the North Fork canyon. A nice mix of wildflowers adorned the road's margins, including some Clarkia biloba and Bleeding Hearts. It takes quite a while to snake through Iowa Hill and Monona Flat and at last reach the very head of Indian Canyon, at Giant Gap Ridge, where we hung a left onto essentially unmarked Elliott Ranch Road, bearing right in half a mile, where Giant Gap Road stays left, and soon we were skimming across the head of Giant Gap Ravine, with views north across Green Valley to Moody Ridge. We passed the southern terminus of the Green Valley Trail; once it continued south to Sugar Pine Guard Station, as can been seen on some old maps, and is also evidenced by a photograph in my possession, of the Tahoe National Forest sign which marked the opposite, northern terminus of the Green Valley Trail. The photograph dates to around 1940.
It was quite a nice sign, in the shape of an arrow, and it read, as I recall, "North Fork American River. Little Switzerland. Green Valley 3. Sugar Pine G.S. 7."
It is funny and nice that Green Valley was named "Little Switzerland." Is it only a coincidence that Joe Steiner, who lived for decades in Green Valley, as caretaker of the Dunckhorst mining properties before dying there, in 1948 ... is it only coincidence that he was once described (scrawled on a slip of paper within a Mason jar, atop his grave) as loving Green Valley, because it reminded him of his native Switzerland?
The recent rains had laid the dust well on Elliott Ranch Road, and we soon reached the unmarked road left to the Hayden Hill Trail; I grabbed my loppers and started cutting back some of the many branches which hung into the road, and heaved a few small downed trees aside, as Ron's truck is a delicate, delicate thing, really too pretty, and it would not do to mar that beauty with a scratch. Ah, one could wish for the good old days, when the previous truck was still alive and well; now, there was a real man's truck, a truck which shrugged off the deadly and many-fingered hands of dead manzanita without the slightest whimper, a truck which just kept forging ahead, an almost inexorable truck, as such things go.
Ah, Toyota.
The roadside vegetation opened slightly and I climbed back in. We slowly advanced to the road's terminus, on the promontory, where a hunters' camp reminded me that, so far as I am concerned, hunting could come to a complete end on public lands. Or, do some hunters have a conscience? Do some hunters not leave mountains of garbage behind? Do some hunters not stand around like idiots, firing round after round from their shotguns, for the sake of making noise, and emptying whole boxes of bullets right in their camping area? I began picking up plastic bottles here, beer cans there, but then I saw quite a quantity of garbage fifty yards down the hill, and realized it was beyond me to even consolidate what the deer season of 2007 had inflicted upon this tiny little patch of public land. The garbage from the deer season of 2006 had been bad enough; I had informed Tahoe National Forest of the hunters' mess, but nothing had been done. So, a little job has grown into a big job.
Like very much of the Foresthill Divide, this area is blanketed by thick, quasi-horizontal strata of Mio-Pliocene andesitic mudflows. It might be better to assign all these mudflows to the Miocene. Beneath these ridge-capping andesitic debris flows are older Miocene rhyolite ash flows. Some of these latter were pyroclastic flows, and became welded tuffs, but this far west, more commonly they were reworked and redistributed by water. We can still call them tuff. Rhyolite tuff. While the source of the younger andesitic flows was along the Sierra crest, the source of the older rhyolite ash seems to have been in central Nevada. This fairly recent discovery supports the classic model of Sierran geomorphology, in which the entire range has been recently tilted up, like a trap-door, with the "hinge" buried beneath the young sediments of the Central Valley, and the Sierra crest forming the long high edge of the tilted block. For, those volcanoes in central Nevada could not have delivered such vast volumes of rhyolite ash to the west slope of the Sierra, if the crest had stood as high as it does today. In particular, those pyroclastic flows which gave us the welded tuffs of higher and middle elevations had to be flowing downhill. It appears the crest has been uplifted around 5,000 feet over the past few million years. There, near the sources of the andesitic lahars, the whole volcanic section thickens, and we see mudflows stacked up, 1500' thick and more. Rarely, basalt flows are preserved in valleys within the vast and often chaotic section of mudflows. For, multiple episodes of erosion punctuated the eruptions; the eruptive phases likely have been far outstripped by the erosive phases, in absolute time, in duration. Time enough for canyons or valleys to form in the mudflow land surface. Whatever came next, eruptively, be it more mudflow, or basalt, or volcanic ash, whatever, would tend to fill those nascent valleys. A new mudflow surface is created, and now it endures a prolonged phase of erosion. New valleys are cut, which are in turn filled by the next eruptive sequence ... .
This area was, it seems, burned over in the 1960 "Volcano" fire, which started over in the Middle Fork American side of things, in Volcano Canyon, and then swept north and east on the Foresthill Divide, reaching Humbug Canyon, and Westville, and even crossing the North Fork American to burn parts of Sawtooth Ridge.
Quite a lot of bulldozer activity took place during and just after the Volcano Fire, and the fire breaks and mounds of dirt can be seen to this day. So far as the Promontory goes, it seems the bulldozers made several swaths, perhaps pushing fuels from the top of the promontory down and over the sides. As a result the old trail leading down to Hayden Hill had first been obliterated around 1960. Ron and I just started wandering down the nose of the ridge, bearing north and east, and soon reached an almost level reach of the Promontory Ridge from which we could see down and west to the heavily forested Terrace. The old trail followed this ridge crest north, until it reached the Terrace, and broke west towards Hayden Hill.
However, a ~1980s Tahoe National Forest clearcut, directly along the line of the trail, served to obliterate it just above the Terrace, and the brush-infested plantation of small Ponderosa Pines was too dense to permit trying to stay on the original course, so we peeled away west, dropping into the Terrace Forest, and soon reached the nearly level road which extends far to the east into the Sugarloaf Basin, and west into the headwaters of the east fork of McIntyre Ravine.
Soon we reached a road bulldozed upon the line of the old trail, perhaps during the Volcano Fire and its aftermath, or perhaps during the 1980s clearcut activity. There we found the section corner common to sections 5, 6, 7, and 8 of T15N, R11E. All the townships in T15N in this area reflect the difficulties faced by early surveyors. A township is supposed to be a six-by-six square array of thirty-six one-mile-square sections. However, the townships in T15N all seem to show a northern tier of six sections which are about one mile east and west, but run about two miles north and south. Hence all these townships verge towards forty-two square miles in extent, instead of thirty-six.
At the section corner a modern monument, consisting of a two-inch diameter galvanized pipe with a marked cap, was accompanied by an older monument, a length of ore-cart track driven into the ground, with its own inscrutable markings. Large trees nearby also contained little signs. Below, to the north and west, is an old cabin site, a mining ditch, and some collapsed tunnels. Presumably a bit of Eocene-age river channel is buried beneath the roughly 400-foot-thick section of "young volcanics" in this area. Possibly the ore-cart track marked one corner of a mining claim.
From here the old trail, now an overgrown road, bears west. We followed along, passing the almost invisible fork right to Hayden Hill itself, coinciding with the trail as depicted on the USGS 7.5-minute "Dutch Flat quadrangle, and soon a mining ditch was crossed, the road dropping below the ditch, then rising to coincide with the ditch, thus obliterating it. This ditch drew water from springs to the west, delivering it to the mine site near the section corner. It is near the 3800' contour.
The bulldozed road, thankfully, came to an end. The trail continued, roughly following the line of the ditch, which was not always evident. The deep impressions of bear feet dotted the ground; they like to step in the same spot each time they walk a favorite trail. It is, in its way, a historic trail, one which likely was never drawn on any official map, but which saw use for centuries, for millenia, being after a fashion the "most-natural" and easiest way to traverse these slopes, for all sorts of animals, including humans. If one were walking from Iowa Hill to the Hayden Hill mines, either those up high, by the section corner, or those below, in Green Valley, one might well peel off the canyon rim at the head of McIntyre Ravine, and follow this old Terrace Trail east to Hayden Hill. One would then avoid an unnecessary climb of two hundred feet, to the now garbage-strewn Promontory, where the "official" Hayden Hill Trail begins.
Continuing west, we entered an area of old-growth forest containing some very large trees. There were Douglas Fir in the six- and seven-foot diameter range, and many large pines and cedars. The whole area screamed of abundant ground water, which in turn suggests that the heavily forested Terrace coincides with the rhyolite ash strata. Almost always, these rhyolite ash strata are associated with springs and seeps. Almost always, the strata themselves are not exposed at all, buried beneath deep soils, developed over many millenia. Almost always, a belt of enhanced forest marks these wet slopes.
Here, on the Terrace, about half a mile west of Hayden Hill, the ground water breaks out in big springs, surrounded by heavy timber, with an understory of robust Bigleaf Maples and Pacific Dogwood, but also, notably, quite a few Pacific Yew and sharp-needled California Nutmeg. So it is a rather fascinating area, botanically, and biogeographically. One rarely sees these Pacific Yews, and more rarely yet, yews as large as here on the Terrace. These springs are at the head of the East Fork of McIntyre Ravine, which joins the North Fork American in Green Valley.
Beyond the big springs, with their yews, and masses of delicate Lady Ferns, and bear-churned black mud, the trail continues, but much less distinctly. It is almost a case of too much of a good thing: the Terrace is broad enough, the forest, open enough, that no one particular route much commends itself over another. The game follows many paths. We strolled along, rarely seeing what could convincingly count as the line of a single, distinct, historic human trail. Here as so often elsewhere, modern use by game is enough to blur and disguise historic use by humans.
Finally, the Terrace seemed to pinch out, and we we reached an area where a bulldozed fire break, dating from the Volcano Fire, had been cut from the rim of the canyon on a steeply-descending course, bearing roughly north, right at the base of the rhyolite-enhanced forest, and just above the serpentine-stunted vegetation below us, in McIntyre Ravine. We found a pleasant little outcrop of serpentine which offered a fine view of the Ravine, with Green Valley and Giant Gap shown to good effect, to the north and to the west. The serpentine here is associated with the Melones Fault Zone. It is in faulted contact with the much-older Shoo Fly Complex metasediments to the east, the fault plane being almost vertical, and striking north and south; and it happens that between the serpentine and the Shoo Fly is a thin screen of Mesozoic metasediments and metavolcanics. If we interpret the serpentine as an ophiolite, as a section of ocean-floor basalt added to North American by continental accretion, and tilted up nearly ninety degrees in the process, this screen of Mesozoic rocks dividing the serpentine (metamorphosed basalt) from the Shoo Fly Complex could represent whatever sediments, possibly intercalated with lava flows, which lay on top of that section of ocean floor. These Mesozoic rocks can be seen to good effect along the river, from the east end of Green Valley, where they include some masses of limestone, upstream nearly to Euchre Bar. They are also evident near the head of the Euchre Bar Trail, on the road to Iron Point, and at Iron Point itself.
I would like to learn more about this Mesozoic screen between the Melones serpentine and the Shoo Fly. It is rarely more than a quarter-mile thick. Sometimes it is invaded by masses of serpentine. Were these masses squished into the Mesozoic screen during accretion, during the Nevadan Orogeny, or do they represent flows of basalt intercalated with the sediments cloaking the ocean floor?
Ron and I struck back east along the Terrace, and found a huge and ancient and recently-deceased Ponderosa Pine, over seven feet in diameter at chest height, and swelling larger still as it rose to split into three massive trunks. We paused to take photographs.
Reaching the almost-invisible fork leading north to Hayden Hill itself, we put our loppers to work opening up the old trail, which follows a nearly level ridge-crest for a quarter-mile before reaching the summit. Another old cabin site is marked by a cellar and odds and ends of sheet metal and glass. Perhaps it burned in the Volcano Fire.
Here the USGS map and TNF map both show the end of the trail. But I had found it continuing down the ridge to the north, last fall, and Ron had found old Forest Service maps which showed it dropping all the way to the river. In fact, a TNF map dating to 1909 showed "Hayden Hill" as a mining camp or settlement of some kind, with a little black square, just as it depicted Damascus, Red Point, and Westville. TNF maps from 1924 and 1930 seemed to show the Hayden Hill Trail dropping all the way to the North Fork. It was our job to settle the issue. Did it really exist? Was there yet another old trail into Green Valley, abandoned for many decades?
The trail is completely buried within manzanita near the cabin site, but it was easy to drop into the open forest to the east and, a hundred yards or so north, rejoin the ridge and the trail. Here a fallen pine, much rotted, has a number of two-by-four steps nailed to its side. When it still stood, whoever lived at the cabin might have climbed the tree, for the amazing view of Giant Gap. But it is a little hard to reconcile the fact that these wooden steps, nailed to the tree, show no signs of burning or scorching, whereas all the vegetation nearby seems to reflect, pretty clearly, having endured the Volcano Fire. Many trees lived through the fire, so it burned cool, and thousands of young conifers sprouted up after it. It is not impossible that here, anyway, it was a fire set purposely to limit the spread of the Volcano Fire.
We continued down the ridge. The trail exists, but it does not always make itself obvious. As we descended, in places we could see that there was a lumber slide, where sawed lumber for the sluice boxes at the Hayden Hill Mine had been dragged down, in bundles, from the canyon rim. One sees these lumber slides all over the place. They take the form of a trench running directly down the slope. Usually they are not at all suitable for a trail, being too steep.
At times there were very-well-defined, too-well-defined, game trails, switching back and forth on the slopes near the lumber slide. As we descended the forest changed from Canyon Live Oak on the steeper ground, with its poorer soils, to Kellogg's Black Oaks, on somewhat gentler slopes, with deeper and better soils.
From a discovering-old-trails standpoint, it was frustrating. A lumber slide cannot count as a bona fide trail. The game trails which switched back and forth could count as human trails, but if so, they were suspiciously narrow, suspiciously poorly-defined. And yet, the overall appearance of the slopes suggested a very active movement of soil and rock and debris of all kinds, downslope; if a trail were not used for, say, eighty years, it could be buried outright on such an actively-eroding slope. If only used by game it would shrink to a narrow track.
We reached the top of one of the huge red mining scars above the mine. These were much more visible thirty years ago; small pines and other trees have gradually populated the scars. The scars derive from hydraulic mining over a century ago. I had never been to the top of the scars before. I scanned the red surface closely; already the auriferous gravels at the Hayden Hill Mine counted as the oldest of the glacial outwash deposits left in Green Valley, as the mine is associated with an abandoned channel of the North Fork, the base of which channel is fully four hundred feet above the river, and the tops of the principal outwash terraces flanking this abandoned channel, six hundred feet above the river. I myself guess these terraces to be roughly 750,000 years old, dating from the Sherwin Glaciation. But the Red Scars rise higher yet. Could one find an absolute highest elevation where glacial outwash is preserved, in these scars?
At the top of the scars, the reddish material had the character of being a very weakly stratified deposit of angular chunks of rock, of an entirely local origin, in a matrix of silt and clay. Were it not for the weak stratification, almost invisible, one would be tempted to name it a colluvial deposit, *not* alluvial at all. As it is, it is about as frustrating as the trail-which-is-not-a-trail we had been following: the deposit has rocks deriving only from the slopes immediately above, and all angular: hence colluvium, hence not glacial outwash. But the deposit is weakly stratified! And it is, whatever its origin and significance, lying on top of true glacial outwash deposits, some distance below.
Well. Interesting, anyway. We followed a game trail right through the Western Red Scar basin, and entered another patch of oak forest, with more game trails, of the kind which with enough imagination might be human trails.
So it was with some frustration that we continued down, zigging and zagging widely in hopes of picking up the line of the "true" trail. Whenever we hit a suspiciously-well-defined game trail, we followed it, in hope that it would become even more well-defined, and settle the issue. On just such a trail we found ourselves approaching a terrace, upon which we could see some relics of mining.
This was just the kind of confirmation we had hoped for.
The terrace was formed by glacial outwash cemented into a tough conflomerate, much as one sees elsewhere in Green Valley, but this must count as the very highest patch of cemented outwash I have ever seen. We were roughly at the same elevation as the top of the Hayden Hill Knoll, a remnant of an outwash terrace flanking the mined-out area. Its summit is just above the 2400-foot contour, six hundred feet above the river. We could see the oak-forested Knoll through the trees, to the north. Between us and the Knoll was a deep ravine.
I told Ron of a buried anvil I had once found near the mine, where a series of terraces and trails flanked the diggings, and we dropped lower yet in search of it. We never found my terraces, never found my anvil, but we did reach one of the huge boulder piles. The Hayden Hill Mine had to get these big boulders out of the way, so they built ore-cart runs to dumps, and, my goodness, left piles of big boulders two hundred feet high. Amazing.
It was fairly overgrown down there, and we had done quite a lot of lopping earlier in the day, upon the Terrace Trail, and on the trail out to Hayden Hill. We didn't have it in us to range widely in search of the Lost Anvil of Hayden Hill, a massive thing, by the way, it must be over two hundred pounds. Well. We did range, but we only ranged up. Unfortunately, we entered a steep wet area choked with maple, dogwood, willow, and all of this very intricately intertwined with poison oak. We climbed directly up through this mad tangle for quite a long time, sweating and huffing and puffing, before breaking out into more open oak forest above. Soon we were back up in the Red Scar, and even struck the very same game trail we had used to enter and traverse the scar. I noticed a very few rounded cobbles of chert, of the sort one sees in Eocene-age relict channels, mixed into the angular rocks of the quasi-colluvium. This confirmed my earlier assessment, that the quasi-colluvium was, to some degree, alluvium; it had been, however briefly, transported by water, and had weakly stratified, as a result. We were fifty to a hundred feet below the tip top of this Red Scar, and there were rounded cobbles of chert. Robbed, no doubt, from an Eocene channel to the east, such as Lost Camp. Or, perhaps, upper Humbug Canyon. Or, perhaps, these chert cobbles came from the putative channel high above us, near the section corner. If this last was the case, then perhaps we should say that the sediments near the top of the red scars are not glacial outwash at all, but very slightly reworked colluvium which rested on top of a glacial outwash floodplain.
Whatever the case, the glacio-fluvial sediments around the Hayden Hill Mine will someday be closely investigated, and will provide evidence of rather old glaciations, in this part of the Sierra.
Ron and I made very slow work of climbing up and out of the great canyon. We were thrashed. Our shirts were wet with sweat. As we climbed, we ranged back and forth, hoping for more definitive signs of a discrete Hayden Hill Trail. We followed the lumber slide, and we ranged back and forth near it, and when we finally did reach the top, we were left with the impression that, yes, a trail did exist, and parts of it can still be followed, but it is often indistinct or even missing.
It occurs to me that the Red Scars might have greatly increased in size since the time the trail was in use. They are in part the direct result of hydraulic mining, and also the result of mining away the gold-bearing glacial outwash deposits below, over-steepening the slopes, which have been sliding and failing ever since.
We reached Ron's truck around six in the evening and it felt very good to just sit down.
Such was a nice day exploring parts of the great canyon of the North Fork of the American River.
The view east from the Promontory, with Quartz Mountain (left), Big Valley Bluff (center), and Snow Mountain (right) in the background.
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