The habitat of the redwood is peculiar. It is found only in a narrow strip, closely hugging ht ePacific coast, stretching from the southern boundary of Oregon or just across the boundary, for there are perhaps 1,000 acres of redwood in Oregon, southward through northern California, nearly to the bay of San Francisco. Indeed, a few scattering groves are found south of the bay, in Santa Cruz county and other localities, and there are evidences that not many centuries ago it extended over the Coast ranges as far south as Los Angeles; but in all this region it is now practically extinct. The densest forests are found in Humboldt county. In Del Norte county, on the north, the area is comparatively small and the forests somewhat less dense; while in Mendocino county, on the south, where the redwood area is even greater than in Humboldt, the forests are not as dense, and in Sonoma county, still farther south, the timber becomes more scattering, thinning out into groves. Its habitat is a region of heavy rainfall, which comes in the winter, and of fogs which sweep in from the Pacific at all times of the year. It is a very moist, temperate region, both of which conditions appear to be essential to the growth of the species. On the north its range is probably limited by temperature, since the humidity is even greater in Oregon and Washington than in California. On the south it is probably limited by the diminishing amount of humidity. The species seems to require for its development a rather nice adjustment of temperature and moisture conditions, which are not found elsewhere, and, as will be seen later, do not at present fully meet the needs of the species, even in its present habitat.
This is probably the densest forest on earth, as measured by the amount of merchantable timber-that is, of timber suitable for the saw-mill-contained per acre. It is not the size of the trees alone which produces this, although they are exceptionally large, even in this state of large things, but it is the great number of trees on each acre, the closeness of their stand. In a red wood forest the sun never shines-it is always twilight. You are, as it were, under the roof of a vast temple, a roof of foliage, supported by great tree columns.
In order to obtain a conception of the enormous stand of timber in the redwood strip, let me commence with some familiar examples for comparison.