A Walk On The San Andreas Fault

Today my College of San Mateo class took a 4.7-mile tour of the San Andreas Fault at Monte Bello Open Space Preserve and Los Trancos Open Space Preserve.

We assembled at the Monte Bello Open Space parking lot on Page Mill Road. We started by examining some conglomerate that was transported 23 miles over about 1.5 millions years of fault movement from the western flanks of Loma Prieta. We then hiked the White Oak Trail, which took us past some magnificent white, black, and live oaks and down to the Stevens Creek. We paused to enjoy the sight of mariposa lillies and globe lillies.  On the way we witnessed the rough alligator lizard mating ritual. The male clamped his teeth onto the head of the female.

As we approached the Canyon Trail Liz Foreman saw something round and white in the forest duff next to the trail. At first I thought it was a mushroom; but when I picked it up we were surprised to find that is was a perfectly intact egg, without a crack in it. It was about 2.6 inches long, and it appeared to have been laid where we found it. If it had fallen out of a nest is would have broken. I have no idea what kind of bird egg this is.

After stopping for lunch, we headed north and uphill on the Canyon Trail, where we observed a pressure ridge on the San Andreas Fault and a sag pond where a bend in the fault caused the land to subside. We then crossed Page Mill Road and entered Los Trancos Open Space Preserve, where we followed the San Andreas Fault Trail for more evidence that we were walking on the interface between two massive continental plates. Posts mark the course of where the land ruptured during the 1906 earthquake.  An offset fence provides evidence of fault displacement.

TO GET THERE... The main parking lot is on Page Mill Road about 7 miles west from Highway 280 and 1.4 miles east of Skyline Boulevard.

A Sunny Spring Day on San Bruno Mountain

It would be hard to imagine a more perfect day to hike on San Bruno Mountain than I had today with my College of San Mateo Peninsula Parks & Trails class. The fog cleared before we commenced and the wind didn't pick up until we were nearly back to the parking lot. In between we enjoyed spectacular views, lots of wild flowers, and mild weather.

From the park & ride lot at the intersection of Bayshore Blvd. and Tunnel Road, we carpooled to the park entrance on Guadalupe Canyon Expressway and then proceeded to the trailhead parking lot. We then headed out counter-clockwise on the Summit Loop Trail, which is rather narrow and nearly overgrown in places with dense vegetation. Because of frequent fog, this park remains green, lush, and wildflowery long after more inland locations have entered their dry season dormancy.

Among the many wildflowers we enjoyed were buckwheat, iris, seaside daisies, asters, red and yellow Indian paintbrush, stonecrop, California perennial phacelia, checkerbloom, and wild onions. The biggest treat was the hummingbird sage, which was in full bloom and quite abundant. It is a native that is quite rare in other places.

We walked past the antennas on top of the mountain

and then stopped for lunch at an overlook with a panoramic view of the Bay Area. We then completed the loop by heading downhill on the Ridge Trail, Summit Loop Trail, Dairy Ravine Trail, and Eucalyptus Loop Trail.

TO GET THERE... From Highway 101 take the Bayshore Blvd. exit in Brisbane. Head north on Bayshore Blvd.  and turn left (west) on Guadalupe Canyon Expressway to the park entrance.

La Honda Creek Open Space Preserve

The final field trip for the Spring session of my Foothill College class took us to the northern part of La Honda Creek Open Space Preserve, which is the only part of the preserve that is currently open to the public. To visit this area you must get a special permit from the Midpeninsula Regional Open Space District that includes the combination to the padlock to the gate at the entrance to the preserve.

First, we walked past a small private inholding that includes the house of the former owner of the property that we were about to explore. We then found the pathway that leads downhill to a large old-growth redwood, which is the only ancient giant left in the area. It was spared because it was the favorite tree of a former owner. We then headed back uphill and on to a faint trail that takes us to a grassy meadow with beautiful views of the mountains, forests, and ocean to the west. We saw lots of beautiful clusters of Douglas Iris, in various shades of blue.

On the way downhill through the meadow, I handed out filaree seeds to some of the students so they could observe how the seeds coil into tight corkscrewsringneck snake, which also obviously didn't appreciate our attention.

when exposed to body heat. At the bottom of the meadow, at an oak grove, I picked up a piece of sheet metal and found a mouse who didn't appreciate being so rudely interrupted. Under another piece of sheet metal we saw a beautiful

We paused for lunch in the shade of an oak tree and then I passed around a can of my bay nut brownies, made with the flavorful nut of the California Bay Laurel, which can be collected in October and November. The rest of the hike involved ascending an old ranch road and returning  to our cars.

TO GET THERE... From Skyline Boulevard, take Bear Gulch Road west and turn right on Allen Road (Private) to the locked gate. You need a permit to access this preserve.