Between San Quentin and the Straits, all about the curve of the bay, winding, wide-mouthed sloughs give access to a land as fertile as Egypt. A slough is a mere wallow of unprofitable waters, waters unused by men and still reluctant of the sea. Pushed aside by the compelling tides, too undisciplined to make proper banks for themselves, they are neglected by all but a few fringing willows and shapeless sycamores in which the herons nest.
Often at evening the white-faced ibis can be seen flying in long, voiceless lines, just clearing the twilight-tinted water, to their accustomed night perches in the wind-beaten willows. They return there, if undisturbed, year after year, accompanied in few and far-between seasons by the egret and the snowy heron, grown man-shy, or if they but knew the purpose for which their nuptial plumage is sacrificed, woman-shy, and seldom seen even by the most wishful eyes.
At Napa a few bull-headed oaks come down almost to the tide-line, and in Sonoma a clump of alien blue gums huddles aloof and unregarded, but from the water little is visible beside the stilted cabins of some gun club or the ramshackle resorts of the flat-nosed, slow craft that wind on mysterious errands between the sunken lands. Whole families of half-amphibious humans appear to live comfortably on these drifting scows, but one never by any chance catches them doing any distinctive thing.
The waters of the sloughs come down from the little inland valleys, where summer nests and broods in a blue haze along the redwood-serried hills. Whether it is white with cherry bloom at Napa, or purple with winy clusters at Sonoma, there is always something interesting going on there of the large process by which granite mountains are made food for man. It is worth a visit if only to learn that a country which does that sort of thing supremely well, finds it also worth while to do it beautifully. Yachting off San Rafael, it is possible to catch at times the scent of roses on an off-shore wind above the salt smell of the marshes.
The last rip of the tide is through the Straits of Carquinez into the back-water of Suisun. From here on, it is a rhythmic heaving to and fro as of well-matched wrestlers, the river-water is set back to Crow's Landing on the San Joaquin, and miles above Sacramento it returns again past Antioch and the Suisun islands. It is lost in a wilderness of tules, through which the sluggish currents blindly wind. Here we have nothing to do with men, our business is all with the tribe of the Little Duck: mallard, teal, tern, coot, heron, eared grebe, and awkward loon.
The tule is a round leafless reed. It springs up along the tide-lands or in the stagnant back-water of the rivers, or by any least dribble of a desert spring. No condition daunts it but absolute dearth of water; far-called, it travels on the wind over mountain ranges, over great wastes of waterless plain to find the one absolute condition, a pool—white rimmed with alkali or poisonous green with arsenic. I have seen it flourish by springs so charged with mineral that each slender column is ringed with its stony deposit, but I do not recall any standing water where tules are not. The stems are filled with papery pith so light that the Indians of the San Joaquin made boats of bundles of them, faggoted together and tied upon a wooden frame.
Year by year the tules reclaim the muddy confluence of the twin rivers. They make an annual growth, die palely, and are beaten down by the wind; between their matted stems the young green comes up again. In the Land of the Little Duck, miles upon miles of them, and not one other thing, stand up on either side the winding water-lanes, man-high and impenetrable.
The Tulare—the place of the tule—is the haunt not only of water-birds but innumerable insect-catchers, and especially of the red-winged blackbirds. In the spring these betake themselves to the reed-fringed marshes in hundreds, building their nests in such neighbourly proximity that the young can hop from rim to rim of the tight-slung, grassy hammocks. Great clouds of the young birds can be seen, just before mating and after nesting in the fall, rising from the low islands of the river-junction. In the season also the male yellow-headed blackbird may be heard singing his sweet but noisy cheering-song to his sombre mate as she weaves marsh grass and wet pond-weed together as a foundation for her home, always prudently completed some weeks in advance of any need of it.
