After a two hour boat ride from Ventura Harbor that included sightings of gray and killer whales, passengers disembarked onto a newly-built pier and subjacent white sand beaches. We had arrived. Once unloaded, the park ranger offered an orientation rejoicing in our good fortunes. The high winds and thick fog which had typified the previous few weeks had now subsided. The forecast for the coming days included sun, low winds, and perfect temperatures.
Fog and wind are omnipresent on Santa Rosa Island and play a major role in shaping the landscape. Any plants with a propensity for upward growth are restricted to canyons, particularly north sloping ones. Here they find refuge from the wind and often more available moisture provided by the meager 15-20 inches of annual rain. However near the highest island peaks–like Black Mountain at 1,300 feet plants have adapted to wind and fog in different ways.
A sequence of five elevated marine terraces along Jug Handle Creek in coastal Mendocino County constitutes a nationally and internationally famous ecological staircase. So outstanding is the combination of canyons, terraces and ancient dunes, tall redwoods and firs, bishop pine forest and dwarfed pines and cypresses that…It has become a Mecca for naturalists, botanists, ecologists, pedologists (soil scientists), geographers and nature-oriented laymen. It is being praised as the best preserved ecological showplace of coastal landscape evolution anywhere in the northern hemisphere.
–Hans Jenny 1973
Throughout the Pleistocene, as the climate fluctuated, sea levels rose and fell in conjunction with the size of the polar ice caps thus allowing oceanic wave-action to cut coastal terraces around the world. Subsequent tectonic forces then slowly pushed these terraces upward. What we now witness in coastal Mendocino County is, as Jenny states, the best preserved ecological showplace of coastal landscape evolution in the Northern Hemisphere.
Through other dynamic processes, beach materials like sand, gravel, clay and other rock have been deposited on the terraces at varied depths. Directly adjacent to the Pacific Ocean on the first step, wind sculpts coastal scrub and grassland on coastal bluffs or “Bonsai” beach and bishop pine forests just inland. A bit further up the staircase, out of reach of the salty air, ample precipitation, Pleistocene and Holocene sand dunes, and deposition of nutrient-rich conifer needles offers the abiotic needs for trees with deep roots and tall shoots. However, the most amazing staircase story begins just to the east of the ancient dunes.
This mountain range had been a place in my dreams for many years. I had heard about its rich conifer forest, that many of the conifers (and other plants of course) common within California reached their southern range extension here, and that a natural fire regime had been ‘maintained’ by mother nature. This was an intact a forest–in as natural a state–as we 21st century explorers might hope to find. The mountains themselves are part of the Peninsular Ranges which I was quite familiar with, having lived in the San Gabriel’s for many years.