On Sunday I joined a field trip led by geologist Allan James ("AJ") as part of the INQUA 2003 conference in Reno. INQUA stands for INternational QUAternary Research Association. Members are engaged in active research bearing upon Pleistocene glaciations and climate fluctuations. The Pleistocene is considered to have begun around 1.75 million years ago, and to have ended a scant 12,000 years ago. Quite a number of glacial advances and retreats occurred. Then the climate warmed, the glaciers receded, and all this warmer period down to the present time is called the Holocene. Since there have been many such warm spells during the Pleistocene, there is nothing to suggest that the cycles of glaciations have actually ended; we are likely just in one more "interglacial" period.
At any rate, AJ has been mapping glacial moraines and till deposits in the upper Bear and South Yuba river basins for the past ten years. He is a professor back East and comes out here every summer to camp up in Rattlesnake Canyon, north of Cisco Grove, and wander the hills, GPS unit in hand, recording glacial features. The most easily recognized of these features derive from the last major glaciation, which in the Sierra is called the Tioga episode.
Around thirty-five people from all over the world were on the field trip. We began at Big Bend, then stopped at a hilltop overlook near Nyack, with fine views of Bear Valley and the Yuba Gorge. From there we drove west to Drum Forebay and caught the old Pacific Turnpike, a road from Dutch Flat to Virginia City, and followed it east into Bear Valley, stopping to examine a moraine deposit which AJ considers to predate the Tioga.
Now, I happen to disagree with AJ about the extent of the Tioga ice; he imagines Tioga ice to be smaller in areal coverage, and thinner, while I see it as somewhat larger and thicker. At every stop we would pile out of the vans and SUVs and AJ would explain this or that. Then I would sidle forward and disagree with most of what he had said. He tolerated this with amazing good grace.
We visited the Yuba Gorge, where the divide between the Bear and South Yuba has been reduced to a low ridge of polished rock of the Shoo Fly Complex. Here, as in many other places, ice from the South Yuba basin overflowed to the south, and broke down the dividing ridge. We then drove up to Rattlesnake Canyon and on to Fordyce Summit, where we visited a moraine AJ regards as especially significant. I offered my usual rebuttal, and then a thunderstorm drove us into the cars. It evolved into a knock-down, drag-out storm of epic proportion, lightning striking everywhere, deafening thunder following immediately after the brilliant flashes, and a truly torrential downpour of rain and hail, which made instant rivers of the dusty roads.
We waited it out and found another high vista point as the skies cleared a little and sunshine broke through. We could see the Sierra crest from Castle Peak down to the Crystal Range, Devils Peak, Snow Mountain, Duncan peak, Cisco Butte, Black Mountain, etc. etc.
We then enjoyed a picnic of wine and beer and crackers and cheese, high on the slopes of Red Mountain; conversation intensified, and debates ripened. I met many geologists, from Germany, Sweden, China, and elsewhere, and was able to learn a little about their own special areas of research. It was a great day.
On Monday I met Ron Gould for an attempt to find and follow an old Tahoe National Forest trail, from Big Bend to Devils Peak and Snow Mountain. We were hoping for a repeat of Sunday's rain, but, although cumulonimbus clouds did blossom, rain was confined to the crest and points east.
We popped into the Big Bend Ranger Station for a quick look at a 1916 map of Tahoe National Forest, which shows many but not all of the historic trails, and marks out areas as "Good Camping Ground" or "Deer" or "Grouse." Among the trails is the historic public trail from the Old Soda Springs Road down the North Fork to Heath Springs.
We had great difficulty, in fact, we failed, in locating the line of the trail on the north, Big Bend side of the railroad. We stumbled along, sweating, on a possible route, littered with logging slash, on an eastward bearing, and as we drew near to the tracks a lone duck appeared. We climbed to the tracks, crossed into a valley leading to a pass we saw as the most likely route, and began scouting back and forth, high and low, for the old trail. After perhaps twenty minutes we found it, marked by blazes on the trees. Soon it became quite well-defined, with many blazes and ducks, and the occasional brushy areas were usually easily passed.
The trail climbed in switchbacks across an open area of glaciated granite, where some blasting had taken place, way back when, to construct or improve the trail. It was by all appearances a large trail, a major trail. It looked as though it had seen fairly heavy use by horses and pack animals, long ago. However, when it passed east into Section 35, T17N, R13E--presumably, being odd-numbered, an old "railroad" section, part of the many many thousands of acres of public land given to the Central Pacific Railroad in the 1860s--the trail became almost impossible to follow.
It was the same old story: heavy logging, with bulldozers scrambling every which way across the terrain, had utterly obliterated the trail. Most of the trees which had borne blazes had been cut down. With great difficulty we continued east, often losing, but always eventually regaining, the line of the old trail. We saw signs, high on the trees, marking the Royal Gorge Co.'s ski trail to Rainbow Lodge. Everything seemed to suggest that this Section 35 was a railroad section which had passed into the ownership of the Royal Gorge Co., but, strangely, it is marked as TNF land on the "big" TNF map. On my special TNF 7.5-minute quadrangle, however, it is marked as private land. Neither map depicts the historic trail to Devils Peak from Big Bend.
At a certain point the trail coincided with a logging road, as evidenced by occasional blazes on roadside trees. This road-with-blazes led us to the northeast corner of Section 35, and into the southeast corner of Section 26 to the north, where two small glacial ponds are nestled in the forest. Continuing, we passed into Section 25 to the east, and stopped for a rest.
I suggested that a side trail must have led more to the south, into a pass between the South Yuba and North Fork of the American, where Nancy Lake is located. This pass is one of many carved by South Yuba ice flowing south into the depths of the North Fork canyon, here, by way of Big Granite Creek. We scouted east through rather hopelessly torn-up terrain, the legacy of logging, without finding anything.
On the way back we were able to recovered a few new strands of the historic trail, including its exact approach to the railroad, but lost it again as we traversed a high knoll of granite, somewhat over 6200' in elevation, due east of Big Bend. We were puzzled by two half-inch cables running up the north face of the knoll. Reaching Ron's truck, we had tallied up something like seven or eight miles on our hike.
However, the story of this old trail continues.
On Tuesday, I visited Eric and Paula Peach in Auburn, and asked Eric about some trails depicted on the "big" TNF map, in the North Fork canyon, near Lake Clementine, Ponderosa Bridge, and points upstream. Eric has a fine collection of maps. As he pawed through his neatly-rolled trove, I spotted an old-style TNF map, and pulled it out.
It was the 1962 TNF map of the Foresthill and Big Bend ranger districts. And there, plain as day, was the old trail from Big Bend to Devils Peak. It showed that, while crossing Section 35, the trail followed a slightly higher line than the road we had walked, and turned south into, and then north, out of, the very pass inhabited by Nancy Lake, before climbing to join the line of the road leading south to Devils Peak from Troy, at the north boundary of Section 6, T16N, R14E.
The map also solved the mystery of the half-inch cables on Knoll 6200; a tiny ski area had been there.
I immediately began poring over this 1962 map with a magnifying glass. I believe I once had my own copy of this map, thirty years ago. Some very intriguing trails were depicted, which I had never realized existed. Like the Big Bend-Devils Peak-Snow Mountain Trail, these trails no longer appear on TNF maps. One such followed the historic Iowa Hill Canal east from Beacroft Trail, past Tadpole Canyon, to the very terminus of the ditch. Another showed a variation upon the route of the Wabena Trail; rather than crossing Wabena Creek and following the east bank down to the North Fork, the trail was shown following the west bank down, and then paralleling the North Fork itself for a mile or so to the west. This lower reach of the trail is exactly that which Ron, my son Greg, and I followed on our recent visit to the Royal Gorge.
This 1962 map also showed the very same historic public trail registered on the 1916 map, from Old Soda Springs Road down the North Fork to Heath Springs. This wonderful trail has been closed to the public (illegally, I would say) for quite a few years now. I had the good fortune to hike it once, in 1979.
Eric kindly provided me with a copy of this 1962 TNF map.