Notes on Population Changes in the Coast Ranges of Northern California By J. O. BROEK University of California, Berkeley In the Coast Ranges of Northern California population growth has been far from uniform. The valley lands have all increased, but since about 1900 many of the rugged portions have decreased or at least stagnated . This paper is a preliminary report on an investigation of this situation , and considers mainly Napa and Sonoma Counties, where most of the field work has been done. Factors contributing to the emigration from the hill lands are : 1.The decline of the lumber industry , as in West Sonoma and South Mendocino Counties. 2.The decline of quicksilver mining in the Mount St. Helena area. 3.The relative decrease of economic opportunity in tne hill lands as compared to the rapid development of commercial agriculture in the lowlands. 4.The general rise in the standard of living, which is more and more difficult to realize. The small scale farmer, and especially the younger people are thus moving out. These negative factors have been— at least partly—counterbalanced by other trends : a. The increasing utilization of the hill lands as recreation areas, particularly in the southern part of the Coast Ranges, due to the proximity -of the Bay Metropolitan Area. b.The influx of retired people who have purchased homes in the hills. c.The establishment of various kinds of institutions (schools, hospitals, Veteran's Plome). This development also has increased the sources of income for other population groups who supply food or perform services. Associated with these changes is a remarkable age composition—a high concentration of the group 65 years and over, and a very small percentage of those 5 years and under (lower than the average for urban population in California). Altogether, there is taking place a shift in the function of the mountains : primary production (agriculture, lumbering, mining) is being replace:! by a secondary function, that of serving the lowlands and the Bay Metropolitan Area for recreation and residential settlement. Also, the ranges are becoming increasingly significant as watersheds for the lowlands. Reforestation and strict control of grazing are desirable as necessary adaptations of the hill lands to new conditions . *This paper will appear in full in the Geographical Review. The Landslide Near Sargent, California By WALTER A. HACKER San Francisco State College Early in March this year there oc- indebted to both ciirred a major mass-movement near Sargent, San Benito County, California . Due to its unusual size and its vicinity to a vital communivation line the feature received wide publicity as the "walking mountain ofGilroy." 1 visited the locality twice, in the comand of Edwin Thomas who recently finished a study on soil slips, and I am of them for contribution of observations. The mass-movement occurred on the north side of an isolated hill which separates the broad valley of the lower San Benito River in the South from the Santa Clara Valley in the North. Qn the San Bautista quadrangle of the Topographic Map this elevation is named "Lomerias Muer-, (38) tas". It represents orographically a southeastern spur of the Santa Cruz Mountains which is separated from the main chain by the canyon of the Pajaro River. The highest elevation in the "Lomerias Muertas" is 1178 feet, a little more than 1000 feet above the floor of the Santa Clara Valley. According to the recently published "Geologic Map of California 1 :500.000" this isolated spur consists of Middle and Lower Pliocene marine sediments which in other localities are known as Fernando, Merced, San Diego , Wildcat series, Ferndale sandstone and others. In the "Lomerias Muertas" it is represented by soft and partly argillaceous sandstones which are interbedded with some layers of poorly cemented limestone conglomerates , thin layers of sandy shales, knses of clay and thin seams of brown coal. The dip of the strata as it is exposed in the excavated "cirque" in the upper part of the slump is about •20° and towards S 30° E. Since a direct connection has been supposed, I should like to mention that the St. Andreas fault line is about 3 miles to the southwest of the landslide, and that no earthquake...
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