A great book, at times a little overwritten, that gives a great, detailed perspective to almost all the elements of San Francisco's natural history, from its geology to its seasonal climate to its trees, fog, physical evolution ... . Great photographs by Michael Bry illustrate the text by Harold Gilliam, former environmental writer and San Francisco Chronicle columnist.
An example of the natural history insight the book offers: did you know that the 1017-acre, three-mile long, lush, green, amazingly treed Golden Gate Park, which anchors the city's northwest end, was sand dunes in the 1860s and took decades of cultivation to get plants to even take root?
And, the ubiquitous California tree, the eucalyptus, is not native - though this is a fairly well-known fact. But still shocking nonetheless for any of us who hike, ride through the stands of the tall, iconic tree of today's California. It was brought here for timber from its native Australia, but by a key oversight the wrong species, the blue gum (one of 600 Australian species), was picked and broadcast, and before the nascent Californians knew it, they had established a thriving area tree that was useless for anything but its being.
The eucalyptus light is not the bright metallic luster of the Lombardy poplars and the cottonwoods of the arid regions or the dazzling mirrorlike glitter of the quaking aspens in the high mountain passes; it is rather a muted scintillation like late afternoon sunlight on the blue-green waters of an ocean cove as seen through the filtering boughs of pines. This special quality of light is partly the result of the arrangement of its leaves ... Look upward from a point near the base of a one-hundred-and-fifty-foot eucalyptus and you see terrace after terrace of foliage, each with its clusters of leaves shimmering with a different vibration as they are stirred by any slight movement of air. It is as if your eyes were moving upward from the base of a Gothic tower as the sunlight illuminated, one after another, successive rising arches and buttresses, spandrels and spires (82-83).
Gilliam spends an admiringly large portion of the book contextualizing the Great Bar, a curving, thin, underwater sandbar that spans the Golden Gate and, in many respects, is inexplicable. Theories swirl around the nearer geological history of the bay; for instance, when a lot of the current seawater was locked up in Ice Age glaciers, the current coastline was 25-ish miles further to the west at the Farallone Islands. One theory suggests that as sea levels rose, the Golden Gate forced the growing ocean to deposit its in-bound sand, forming the Great Bar. Later, when the overall forces of water through the Gate reversed, the sandbar took on its current seaward-bulging shape. The Bar must be dredged to maintain a shipping channel and is not an important feature in and of itself, but offers distinct, physical evidence, laden with concommitant theories of the area's particular natural history.
The most compelling chapter of the book, "The Sky," discusses the Bay Area's weather patterns, in particular the subtle changes in types and timing of seasonal fog with its attendant causes. Gilliam describes how he can, amazingly, wake up in the morning and tell what the weather forecast holds for the day just by sniffing the air from his one-time Telegraph Hill home:
The aromas drifting in the window were sure signs of things to come. If the odor was salty, we could expect cool, breezy weather off the ocean and probably fog. But a pungent aroma from the coffee roasters near the Ferry Building would be borne on a south wind, a reliable indication of an approaching rainstorm. An odor of burning or an acrid tang in the air meant the breeze was coming from the industrial areas northeast of the bay, particularly the oil refineries at Richmond and beyond. The day was sure to be sharp, clear, dry, and extraordinarily cold if the season was winter, or equally clear and dry but unusually warm at any other season (203 - 204).
SF in five movements:
1. The Land and the Waters
2. The Trees
3. The Parks
4. The Wildlife
5. The Sky
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