it owes its immunity from the forest fires which wreak frightful havoc among the surrounding forests. As the redwood is limited to the Coast Range, so the big tree is limited wholly to the Sierra Nevada. Unlike the redwood the big tree occurs in scattered groves (ten in all) among other species. Its habitat extends some 200 m., from latitude 36° to 39°, nowhere descending much below an altitude of 5000 ft., nor rising above 8000 ft. The most northerly grove and the nearest to San Francisco is the Calaveras Grove near Stockton; the Mariposa Grove just south of the Yosemite National Park, is a state reservation and easily accessible to tourists. The noblest groves are near Visalia, and are held as a national park. The average height is about 275 ft., and the diameter near the ground 20 ft.; various individuals stand over 300 ft., and a diameter of 25 ft. is not rare. One tree measures 35.7 ft. inside the bark 4 ft. above the ground, 10 ft. at 200 ft. above the ground, and is 325 ft. tall. Specimens have been cut down that were estimated to be 1300 and even 2200 years old; many trees standing are presumably 2500 years old. It is the opinion of John Muir that the big tree would normally live 5000 years or more; that the California groves are still in their prime; that, contrary to general ideas, the big tree was never more widely distributed than now, at least not within the past 8000 or 10,000 years; that it is not a decaying species, but that on the contrary “no tree of all the forest is more enduringly established in concord with climate and soil,” growing like the mountain pine even on granite, and in little danger save from the greed of the lumberman; but other excellent authorities consider it as hardly holding its own, especially in the north. Three main wood belts cover the flanks of the Sierra: the lower or main pine belt, the silver fir belt, and the upper pine belt. The sugar pine, the yellow or silver pine and the Douglas spruce (considerably smaller than in Oregon and Washington), are rivals in stature and nobility, all attaining 200 ft. or more when full grown; and the incense cedar reaches a height of 150 ft. In this belt and the following one of firs the big tree also grows. The white silver fir (abies concolor) and the silver or red fir (ab. magnifica), standing 200 to 250 ft., make up almost wholly the main forest belt from 5000 to 9000 ft. for some 450 m. Above the firs come the tamarack, constituting the bulk of the lower Alpine forest; the hardy long-lived mountain pine; the red cedar or juniper, growing even on the baldest rocks; the beautiful hemlock spruce; the still higher white pine, nut pine, needle pine; and finally, at 10,000 to 12,000 ft., the dwarf pine, which grows in a tangle on the earth over which one walks, and may not show for a century’s growth more than a foot of height or an inch of girth. The Nevada slope of the mountains below 7500 ft. is covered with the nut pine down to the sage plains. Its nuts are gathered in enormous amounts by the Indians for food; and it is estimated that the yearly harvest of these nuts exceeds in bulk that of all the cereals of California (John Muir). On the Sierra the underbrush is characterized by the pungent manzanita, the California buckeye and the chamiso; the last two growing equally abundantly on the Coast Range. The chamiso and the manzanita, with a variety of shrubby oaks and thorny plants, often grow together in a dense and sometimes quite impenetrable undergrowth, forming what is known as “chaparral”; if the chamiso occurs alone the thicket is a “chamisal.” The elm, the hickory, the beech, the chestnut, and many others of the most characteristic and useful trees of the eastern states were originally entirely wanting in California. Oaks are abundant; they are especially characteristic of the Great Valley, where they grow in magnificent groves. Up to 1910 national forest reserves amounted to 27,968,510 acres. In 1909 Congress created a national forest to include the big tree groves in Calaveras and Tuolumne counties. One of the noblest redwood areas (that of Santa Cruz county) is a state reservation (created in 1901). Even within reservations almost all the merchantable timber is owned by private individuals. In addition to native trees many others—especially ornamental species—have been successfully introduced from various parts of the world.
Soil.—Sand and loams in great variety, grading from mere sand to adobe, make up the soils of the state. The plains of the north-east counties are volcanic, and those of the south-east sandy. It is impossible to say with accuracy what part of the state may properly be classed as tillable. The total farm acreage in 1900 was 28,828,951 acres, of which 41.5% were improved; since 1880 the absolute amount of improved land has remained practically constant, despite the extraordinary progress of the state in these years. Much land is too rough, too elevated or too arid ever to be made agriculturally available; but irrigation, and the work of the state and national agricultural bureaus in introducing new plants and promoting scientific farming, have accomplished much that once seemed impossible. The peculiarities of the climate, especially its division into two seasons, make Californian (and Southern Arizona) agriculture very different from that of the rest of the country. During the winter no shelter is necessary for live-stock, nor, during summer, for the grains that are harvested in June and July, and may lie for weeks or months in the field. The mild, wet winter is the season of planting and growth, and so throughout the year there is a succession of crops. The dangers of drought in the long dry seasons particularly increase the uncertainties of agriculture in regions naturally arid. Irrigation was introduced in Southern California before 1780, but its use was desultory and its spread slow till after 1850. In 1900 almost 1,500,000 acres were irrigated—an increase of 46% since 1890. About half of this total was in San Joaquin Valley. California has the greatest area of irrigated land of any state in the Union, and offers the most complete utilization of resources. In the south artesian wells, and in the Great Valley the rivers of the Sierra slope, are the main source of water-supply. On nearly all lands irrigated some crops will grow in ordinary seasons without irrigation, but it is this that makes possible selection of crops; practically indispensable for all field and orchard culture in the south, save for a few moist coastal areas, it everywhere increases the yield of all crops and is practised generally all over the state. Of the acreage devoted to alfalfa in 1899, 76.2% was irrigated; of that devoted to subtropical fruits, 71.7%. Small fruits, orchard fruits, hay, garden products and grains are decreasingly dependent on irrigation; wheat, which was once California’s great staple, is (for good, but not for best results) comparatively independent of it,—hence its early predominance in Californian agriculture, due to this success on arid lands since taken over for more remunerative irrigated crops.
Agriculture.—The spread of irrigation and of intensive cultivation, and the increase of small farms during the last quarter of the 19th century, have made California what it is to-day. Agriculture had its beginning in wheat-raising on great ranches, from 50,000 even to several hundred thousand acres in extent. A few of these, particularly in the Great Valley, are still worked, but only a few. The average size of farms in 1850 (when the large Mexican grants were almost the only farms, and these unbroken) was 4466 acres; in 1860 it was 466.4, and in 1900 only 397.4 acres. Stock ranches, tobacco plantations, and hay and grain farms, average from 800 to 530 acres, and counteract the tendency of dairy farms, beet plantations, orchards, vegetable gardens and nurseries to lower the size of the farm unit still further. The renting of large holdings prevails to a greater extent than in any other state except Texas. From 1880 to 1900 the number of farms above 500 and below 1000 acres doubled; half of the total in 1900 were smaller than 100 acres. The most remunerative and most characteristic farming to-day is diversified and intensive and on small holdings. The essential character of California’s economic life has been determined by the successive predominance of grass, gold, grain and fruits. Omitting the second it may be truly said that the order of agricultural development has been mainly one of blind experiment or fortuitous circumstances. Staple products have changed with increasing knowledge of climatic conditions, of life-zones and of the fitness of crops; first hides and tallow, then wool, wheat, grapes (which in the early eighteen-nineties were the leading fruit), deciduous orchard fruits, and semi-tropical citrus fruits successively. Prunes were introduced in 1854, but their possibilities were only slightly appreciated for some thirty years. Of various other crops much the same is true. Of late years