Wednesday, June 22, 2005

Return to Secret Canyon and the Iowa Hill Canal

On Tuesday morning I met Catherine O'Riley and geologist/paleontologist Dave Lawler at Weimar for a visit to Secret Canyon and the Iowa Hill Canal. We crossed the North Fork on Ponderosa Way, where a tremendous bloom of Clarkia purpurea, Purple Clarkia, or Wincecup Fairyfan, is in progress along the old wagon road, as it drops into the canyon. These spectacular flowers have four pinkish or lavender petals grouped in a bowl, each with a purple spot. There is a ring of white anthers at the base of the corolla-bowl, and the four-parted stigma is a deep maroon.

We stopped to photograph these lovely flowers.

There are many species of Clarkia in California. They are in the Evening Primrose family. Recently I have been photographing another species, Clarkia arcuata, with a cream to white stigma, and dark blue anthers, near the head of the Green Valley Trail, on sunny serpentine slopes. This C. arcuata may be the flower I mistakenly identified as a Sidalcea near Giant Gap, about a month ago.

The road up the south wall of the canyon is rough and rocky. Eventually we won through and drove the twenty or so miles up the Foresthill Road to Ford Point, at about 5600' elevation. A deep blue sky was adorned with scattered fair-weather cumulus clouds, driven north by strong south winds. What would have been quite a warm day at lower elevations was markedly cool.

We took the same little road breaking east from the Ford Point road, a road marked 13-14-2 as I recall, into a logged area rich with green manzanita which scratched my little Subaru. Again the Subie managed to collect pine needles in its catalytic converter housing, and a delicate perfume of burning pine wafted about as we parked and gathered our packs. I looked beneath the car and reassured myself that nothing too significant was afoot; it would not do to set Tahoe National Forest afire.

The country rock is metasediments of the Shoo Fly Complex. The Complex is divided into four major thrust blocks, each containing various formations which have never yet been systematically mapped, except in this area, by David Harwood of the USGS. He identifies the rocks of Secret Canyon as belonging to the oldest thrust block of the Shoo Fly, the Lang sequence, and divides this Lang Sequence into formations such as the Big Valley Bluff fm., the Screwauger Breccia, etc.

At any rate, there are not very many exposures of the bedrock here, almost everything being covered by a glacial till which itself contains these same Lang sequence rocks, with few to no exotic rocks from outside the area. The till makes for rich soils which do a good job of storing the snowmelt and support much in the way of heavy timber, especially on the more northern exposures.

On a pure south slope near our parking spot, Ponderosa Pines grew. Large Sugar Pines and Douglas Fir were in the area. But across Secret Canyon to the south, on the northern exposures, these same ancient Sugar Pine and Douglas Fir are mixed with some large true fir such as White Fir and, rarely, Red Fir, with an understory of small to fairly large true fir.

We followed the road east to its end, where a short trail drops to the Secret Canyon Canal (SCC), a tributary to the Iowa Hill Canal (IHC). Suddenly all signs of logging disappeared and we all felt that this was a very special trail, almost level, winding through the forest of huge old trees. We passed the half-crushed shingled cabin and reached the "take" from Secret Canyon, where a log dam likely once diverted the creek into the SCC.

Directly across Secret Canyon and 25 feet higher is the American Hill Canal (AHC). We crossed and climbed over rocks to the old ditch, there, a wooden flume, with a surprising quantity of flume wood still visible on the ground.

It looks as though the flume, its most recent incarnation possibly dating to the 1930s, had been robbed for its lumber at some time, possibly for the cabin across the creek, and for whatever mining operations had been underway there.

At any rate, the main body of the wooden flume is gone, with parts of the floor remaining, and no signs of a fire have affected the area since the flume was built, perhaps seventy years ago.

We followed this American Hill Canal back down Secret Canyon to the west, until the first little "ditch lake" is reached, where a generous array of springs fill the old canal over a distance of over a hundred feet. We rested and ate and explored before turning back; there was only so much time, if we wished to visit the IHC.

At Beacroft we saw an SUV with a trailer and some kayaks. Soon we were at the pass, just beyond where the Beacroft Trail climbs away west, and entering a grove of White Fir, found and followed the little old road by which lumber for the giant IHC flume was hauled to the work. This part of the flume was necessary to cross the cliffy areas on both sides of Tadpole Canyon. Here, in contrast to the AHC in Secret Canyon, several wildfires had intervened since the flume's principal period of operation, in the 1870s, and only a very few fragments of almost unrecognizable flume wood remained.

However, the bench cut blasted from the cliffs makes for a very nice trail, in fact, the entire upper few miles of the IHC is shown as a trail on the 1962 TNF map of this area. It is fairly easy going and the old flume-trail offers great views into and across the North Fork canyon, here over 3000 feet deep. The big waterfall near the bottom of Big Valley Creek is still impressive.

Very much yellow-flowering Stonecrop was in bloom on the cliffs along the IHC trail, mixed with a red-purple profusion of Penstemon, possibly that species called Mountain Pride.

Tadpole Canyon creek has subsided quite a bit over recent weeks and we crossed by an easy jump and continued along on the IHC as it curved from north to east and reentered the main North Fork canyon. There the brush becomes extreme and further progress is barred. Green Manzanita, Huckleberry Oak, and Bush Chinquapin dominate. We had fine views across the North Fork to Sugar Pine Point, Cherry Point, Snow Mountain, and in the distance to the north, Castle and Basin peaks.

The Big Waterfall in Big Granite Creek is still big, and looks quite monstrous in fact. It would require quite a hike to actually visit the thing. It could be approached from above, from the Loch Leven Lakes area, but quite a bit of brush guards the entrances to Big Granite Canyon in that area.

The shadows lengthened and added considerable drama to the great and deep canyon of the North Fork American. We had a schedule to meet and had to leave a little earlier than we would have liked.

I have not seen, yet, the larger part of the Secret Canyon Canal. Maps suggest that it has been disrupted by logging and logging roads over much of its course in Little Secret Canyon. More exploration is needed. If it had been left intact, one could treat that uppermost part of the IHC, the SCC, and the AHC as one continuous trail, almost perfectly level, winding along through the main North Fork canyon, Tadpole Canyon, Little Secret Canyon, and Secret Canyon, for a distance of, say, almost ten miles.

It was a great day in and around the great canyon.

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