Edges. I like edges; they add flavor, a bit of sharpness, and diversity to life. In the natural world some of the richest biological regions are edges. You know this intuitively. When you visit a mature redwood forest, it is often profoundly still and quiet, no mammals and few birds. And a stroll through an open grassland is also apt to be a bit boring. But hang out at the edge, where the forest meets the grassland. Here there is an increase in life and activity. At this interface exists a greater variety of habitats and niches ‑‑- opportunities for plants and animals to exploit. Biologists have even coined the word, “ecotone”, to describe this location.
Temporal edges. Many mornings I jog on the Bear Valley trail before dawn. It is often completely dark when I begin my run; I have to strain to see the trail. And as the earth turns toward the sun, the light slowly comes. It’s nearly imperceptibly at first. But gradually the trees, leaves, and rocks take form and by the time I’m back to the car, I can see the world clearly. I have experienced the edge called dawn.
Life edges. I make a living as an itinerant naturalist and I’m married to a free-lance artist. We definitely live on the financial edge. In everyone’s life there are edges: birth, graduations, new jobs, marriage, babies, divorces, and the ultimate edge — dying.
Geologic edge. Since moving to Marin many years ago I have literally lived right on the brink, straddling the San Andreas fault – that most dramatic edge between the Pacific and the North American plate. Not only have I lived on it but I have traversed a good portion of it. It’s a long one and has many faces. Along this fault I have climbed through jungles and peered into volcanoes in Costa Rica, sailed beside blue whales in the Sea of Cortez, watched thousands of white pelicans soaring over the Salton Sea, photographed wildflowers on the Tejon Pass, seen coyotes lope across the Carrizzo Plain, illegally swum in the Crystal Springs Reservoir, driven through the Olema Valley more times than I can imagine, tidepooled in the eelgrass beds in Bodega Bay and climbed the historic Pt. Arena lighthouse.
And this past weekend I spent some time at yet another facet of the San Andreas fault, the Pinnacles National Monument. This scenic, rocky wonderland is off Highway 25, about 37 miles south of Hollister in San Benito county.
The Pinnacles are what is left of one/half a volcano. About 23 million years ago an eruption built an 8000′ mountain right on the San Andreas fault. As the two plates began to slide apart half of this volcano headed north and the rest was left behind. The southern part is still there, albeit a bit smaller, 195 miles away near the present day city of Lancaster in the Mojave Desert. The Pinnacles National Monument encloses what’s left of the northern half. Water, ice and wind has worn it down to a spectacular jumble of 2500′ jagged peaks.
The Pinnacles were declared a national treasure in 1908 by the only Republican environmental president — Teddy Roosevelt. This park is famous for a number of things besides the remarkable geology: the spring wildflower display, the “caves” (actually steep canyons full of giant boulders), nesting prairie falcons and Golden Eagles, incredibly hot summers, and inordinate numbers of Boy Scouts.
On my recent trip we saw two pairs of prairie falcons, a golden eagle on a nest, and acres of wildflowers especially “shooting stars”. We hiked through one of the caves (the other was closed due to flooding) and we had the misfortune to camp by Troop 126.
So if you like hanging out on the edge (of cliffs and tectonic plates) and discovering new sections of “our” fault then put the Pinnacles National Monument down on your long list of places to go someday.