16. Quercus Sonomensis, Benth. (Black Oak.)
San Diego!! Anderson Valley! Auburn!
Eastern and northern hillsides in the Coast Ranges. It also occupies the more easterly-situated flats, among the redwoods, wherever they are too dry for redwood. Very seldom it is found in the valley; and when found, it occupies that portion of it which is adjacent to the hillsides, where there is generally a gravelly soil. It is always a middle-sized tree, having mostly numerous erect branches arranged like those of Acer saccharinum. In fall it sheds its leaves, which become buff-colored, before any other of our deciduous oaks. The wood of this tree is of a poor quality; used for fuel only.
17. Quercus chrysolepis, Liebm. (Drooping Live Oak.)
The most rare of all our oaks; it bears acorns but seldom, and even then very sparingly. I have not been able to satisfy myself whether they are biannual or not, but I am rather inclined to believe they are. Northern slopes near Cloverdale! in Anderson Valley! and near Forest Hill! Tree 30-40 feet high, with a rather smooth whitish bark, and mostly long, slender, drooping branches; evergreen. Of the quality of its wood I could not learn anything from settlers. The tree being rare, and occupying always moist slopes along gulches, it is not often cut down.
18. Quercus densiflora, Hook. (Chestnut Oak.)
Along the Coast Range, associated with the redwood, increasing northwards; from Santa Cruz to Mendocino City, at least, it occurs only in or close by the redwoods. This tree attains rather a large height in dense woods, and is then but sparingly branched. Leaves and acorns very considerable. Its wood is absolutely useless; it is very coarse grained, and like the redwood wet like a sponge when cut; it is extremely perishable. At Mendocino City log-men call it Water Oak.
19. Castanea chrysophylla, Dougl. (Chestnut.)
On the Oakland hills this species is but 3-6 feet high; blooms about the fourth of July, like the Eastern Castanea vesca, and bears perfect fruit. On the so-called plains at Mendocino City, however, it is a large tree, averaging from 50-125 feet in height, and 2-3 feet in diameter. Those trees were completely covered with blossoms on the twenty-third of September, 1865; settlers say they never found its fruit. Here, on the Oakland hills, it grows only on the outcropping of a white friable slate, destitute of all vegetable remains; at the Mendocino plains it is found to grow on a cemented gravel, upon which the water rests for some months after the rainy season. The supply of an aerial moisture during the dry season is in favor of the Oakland hills, judging by the lichenose vegetation of the two localities.