Saturday, January 16, 2016

The Valley Oak near us

Nearby Valley Oak, from our San Rafael backyard.
The valley oak (Quercus lobata) that grows within view of our backyard towers high over the block. Here, a tuft of passing storm cloud gives it a timeless backdrop. This cloud is sweeping from right to left, as the wavelike pattern on its top edge might indicate. This was during our first rain event of the fall, about two months ago. (And the blaze of color is thanks to this being the 37th frame on a 36-exposure roll of film.)

We are lucky to live in a microclimate warm enough for the valley oak to tolerate. Where we lived until August last year, in Tamalpais Valley, just on the other side of the 2,572-foot-tall Mount Tamalpais, it was too cool and fog-influenced for this species. That was less than 7 miles away, but as the name implied, it was in a valley, which tends to trap cooler air. This was noticeable in the summer, when fog would sometimes roll in from the nearby Pacific by 4pm on summer days--if it was sunny at all.

Here, in San Rafael, we and our neighbors own window-unit air conditioners that stay very busy in July and August; but we get to enjoy the presence of the valley oak. This tree can rise to a height over 100 feet, and boast a trunk over six feet thick. According to my naturalist friend Josiah, the valley oaks in the area are the reason that we frequently enjoy a pair of white-breasted nuthatches visiting our backyard. This, too, is a species that would be nearly unthinkable to see in Tam Valley.

For my birthday last year, my friend Mike gave me the excellent Oaks of California (Cachuma Press, 1991). This paperback is a wonderful guide for those interested in California's oak diversity, wildlife associated with oaks, indigenous peoples' use of oaks, and where to find the eight oaks of California. I recommend it for anyone (even if not in California) interested in the overall majesty of the oak.

When I first received this book, I had little knowledge of the valley oak or where it lived. I had no idea I'd be able to see one from my backyard in a year. I longed to see what was described in the passage below, quoted on page 11 of the book. It was written by surveyor William Brewer in 1861:
First I passed through a wild canyon, then over hills covered with oats, with here and there trees -- oaks and pines. Some of these oaks were noble ones indeed. How I wish one stood in our yard at home. ... I measured one, with wide and spreading and cragged branches, that was 26.5 feet in circumference. Another had a diameter of over six feet, and the branches spread over 75 feet each way. I lay beneath its shade a little while before going on.
In our neighborhood, redwood and sequoia trees have also been planted. I imagine they were planted by those inspired by seeing them in regions of California where they take on their full majesty. Here, they are wind-pruned and stunted. The only giant here is the valley oak.