P.G.&E. Road Trail (Topo #29)

This dramatic and scenic hike offers spectacular views of present and past quarrying
operations that created the canyon with sheer moss and lichen covered walls.
Participants will have the opportunity of hike into the Quarry at two
different levels to explore some unique geology and natural history of this
area.
Since parking is limited along Hwy 49 at the beginning of the hike, we will shuttle
participants two miles from the meeting location to the top of the canyon
where the hike will begin, just to the west of the Quarry.  After hiking
down the Quarry trail to the river, we will hike back the Quarry Road to the
parking lot where you left your car.
The hike will proceed along a relatively new trail outside the recently
installed chain link fence designed to keep people from entering the active
quarrying area.  The trail crosses the PG&E gravel road and proceeds along
an old access road into the two middle levels of the quarry. 

Bring a snack and water depending on the time you plan to spend in the
canyon.  (shortest time will be about 2 hours, longest might be 4-5 hrs.) 
The caverns of the quarry are great locations for lunch, snack, or just
enjoying extra time in the area.
Some basic geology features make this area unique.
Most of the surrounding canyon rock consists of ancient marine sediments of
the Paleozoic era, with the limestone likely formed as a result of coral
reef activities at that time.  Later in two general uplifts, one in Jurassic
times (250 MYA) and again about 5 million years ago the ancient sediments
including the coral reef  was uplifted and  folded into its present state
which is generally referred to as the Calaveras Formation.   The limestone
in this region is a part of a ridge of limestone running from Calaveras to
Lake Oroville.    As you look across the river you can see the outcropping
limestone on the other side of the river. This is the same limestone
formation that is exposed at Lake Clementine and contains the limestone
caves in the Jackson area.  Quarrying operations started in the 1900’s,
continuing today.   The limestone is extremely pure, early 97% Calcium
Carbonate.  The limestone from this quarry has been used in the processing
of sugar beets, (Spreckles Sugar Co.), and for production of cement, ceramic
tile, and construction aggregate.
Some basic Biological features:
This region would be considered to be the foothill Pine-Oak woodland, with
examples of a good transition of Oaks, Pines, and Shrubs as the trail
descends in elevation into the riparian community of the river.  Common
vegetation includes: Canyon Live Oak, Black Oak, Blue Oak, Interior Live
Oak, Big Leaf Maple, Madrone, Ponderosa Pine, Foothill Pine, Douglas Fir,
Manzanita, Toyon, Buckbrush, Deerbrush, Yerba Santa and Scotch Broom.  There
will be some annuals in bloom, possibly a forget-me-not called Hounds
Tongue, some buttercups, and Popcorn Flowers.   Typical ferns of the area
include: Gold-backed fern, Bracken, Licorice, and Maiden Hair.  Rocks and
cliffs have beautiful displays of lichens, mosses, and stone crop(Dudleya
and Sedum) with the great combination of moisture and warmer temperature
this time of year.

The above description of our March 9, 2002 hike was prepared by member/leader Ernie Riley.  Ernie is a retired college teacher of such subjects as:  biology, California natural history, zoology and ornithology.