on the Peninsula. Where the fault crosses the ridge at the top of Los Trancos Open Space Preserve, the crushed rock has eroded to form a fault saddle. Sag ponds at the preserve result from horizontal fault displacements that shifted hill slopes, blocked ravines, and created undrained depressions. Earthquake movements have changed stream courses along upper Stevens Creek Canyon. Landslides occur frequently in the steep Santa Cruz Mountains; many were triggered by the 1906 and 1989 quakes and their prehistoric counterparts.
The San Gregorio Fault runs northwest-southeast inland from the coast on the west side of the Santa Cruz Mountains. Its effects are seen in the shifts of creek directions near Butano State Park, at Fitzgerald Marine Reserve, and near Mussel Rock.
Plant and Animal Life
In this guide we mention some of the trees, flowers and creatures you may encounter, but we can touch only briefly on a few of the many species. Following are brief descriptions of the major plant communities. Fortunately for those whose curiosity is aroused, there are many excellent publications that focus on the plants and wildlife of the Bay Area and California. See Appendix II.
More than 1700 species grow in the Santa Cruz Mountains and on their western and eastern flanks, categorized into what are known as plant communities—a group of plants with similar tolerances and similar adaptations to environmental conditions.
On the east side of the Skyline ridge there are four main plant communities:
1. Mixed woodlands—characterized by the rounded forms of the oaks, madrones, bays, and buckeyes that cover much of our hillsides.
2. Open, rolling grasslands—a noticeably different community of mountainside meadows and foothill pasturelands. Mostly imported annual grasses, they are green in winter, dry and golden in summer, and characteristic of California and other Mediterranean climates, distinguished by winter rains and summer drought.
3. Conifer forests of firs and redwoods—tall, evergreen trees that cover thousands of acres in the Skyline ridge watersheds, parks, and sheltered canyons. Although the redwoods were cut over in the 19th century, extensive stands have grown again.
4. Chaparral—a dense growth of shrubs and trees specially adapted to winter rains and long, dry summers that thrive on hot dry slopes. Their leathery or waxy evergreen leaves, sometimes curled inward, conserve moisture, and their long taproots reach water deep below the surface. These plants form a scratchy thicket, unfriendly to the hiker but home to many species of wildlife. The Spaniards are said to have named the vegetation “chaparral” after a Spanish evergreen oak, the chaparro.
Coastal Trail south of Miramontes Point
On the west side of the Santa Cruz Mountains, heavy winter rainfall and summer fog nurture a thick forest in the canyons and on the upper slopes. Up to 60 inches of rain falls in wet years, about 45 inches in normal years. Summer fog is formed when cold water beside the coast upwells to the surface and chills the moisture-laden air above, causing condensation. The rising hot air inland creates a partial vacuum, into which foggy air flows.
The west side has three main plant communities:
1. Giant coast redwood trees—the moisture encourages lush growth in southern San Mateo County and nurtures associated Douglas firs; tan oak and bay laurel trees grow among these conifers until they are shaded out by the taller redwoods.
2. Grasslands—found on exposed west- and south-facing ridges, making sunny pockets scattered along the trails. They are either native grasses or introduced species.
3. Coastal scrub—a softer version of chaparral found on the coast itself, where the winds are strong and the salt spray pervasive, covering consists of some native grasses and introduced species that cover most of the coastal terraces and bluffs.
Fauna—You will also see and hear numerous birds, and if you look closely you will notice lizards, salamanders and the myriad spiders and insects of the earth. You may see a squirrel in the trees or an occasional rabbit in the brush. Larger animals, once so plentiful, are now seldom seen, though you may have the pleasure of catching sight of a deer in the woods or an occasional coyote in the grasslands. Mammal predators such as gray foxes, coyotes, bobcats, and even an occasional mountain lion live in the wild areas.
Footprints in the wet earth by a stream or in the dust on a sunny trail will tell you there is still animal life nearby. Small holes in the ground and tunnels underfoot are probably all you will see of the many burrowers, such as badgers, voles, field mice, and gophers. In thick woodlands you may find the three-foot-high piles of sticks that are the homes of woodrats. Along the San Francisco Bay Trail there are a few places where small populations of the burrowing owl are still extant.
The Peninsula’s and Coastside’s Past
Although humans have lived on the Peninsula for at least 3000 years, it is only in the past 200 years that they have significantly changed the natural landscape. Spanish newcomers in the 18th century hunted game with their guns, brought herds that grazed the hills, and introduced annual grasses that supplanted the native bunchgrass. By the mid-19th century, Anglos from the East were changing the face of the Peninsula, logging over the forests and farming the valleys and foothills.
But it was not until the mid-20th century that the settlements scattered down the length of the Peninsula suddenly spread over the valley, reshaped the hills, and replaced woodlands and orchards with houses, roads, and shopping centers.
However, the Bayside, which four decades ago was seemingly about to be engulfed in buildings, is now witnessing renewed efforts toward containing its urban spread. Public and private groups are setting aside parks, preserves, and trail corridors that complement the increasingly dense settlement patterns of the Bayside. An expanding system of public greenbelts now gives us the opportunity to walk through the lovely foothill landscape, follow a stream, or climb a trail up our steep mountains to thousands of acres of forest on both sides of the Skyline ridge. Public beaches and a coastal trail offer access to the length of the San Mateo County Coast. A walking and bicycling trail on the Bay’s shore extends from the San Francisco to Palo Alto with only a few gaps. The total size of public parklands in the area covered by this book is more than 60,000 acres. Peninsula and Bay Area residents are fortunate that foresighted citizens urged the state and counties to buy so much beautiful, unspoiled land for public parks. It is the goal of this guide book to help the reader explore all the wonderful parks and preserves lying on both sides of the Skyline ridge from the San Francisco County line to roughly the area north of Highways 85 and 9.
Earliest Inhabitants
The first people to walk these hills were the Ohlones, a tribe of hunter-gatherers who lived along the Bay and Pacific shores and in the foothills between San Francisco and Monterey. When the first European explorers came to the Peninsula, they found their way crisscrossed by trails worn by these Native Americans as they went from their creekside villages to the shores of the Bay, into the hills, and across the mountains to the coast. Before the Spanish era the Peninsula supported one of the densest Native American populations in the country. Nearly 10,000 Ohlones lived between San Francisco and Monterey.
The Ohlones lived well without cultivating the land. They thrived on the incredible bounty of Peninsula woodlands, streams, and shores. Elk, deer, antelope, coyote, fox, bear, and mountain lion roamed the hills, along with plentiful small game. Birds, particularly waterfowl, filled the air in sky-darkening numbers. Acorns, the staple of the Ohlones’ diet, were gathered from the thick stands of oak in the hills and on the valley floors. Families returned to ancestral groves year after year
