CALIFORNIA SOILS RICH. 41 



several feet and material from such depths, when thrown 

 on the surface, is nearly or quite as fertile as the original 

 surface soil. In the case of a cellar dug near Nevada 

 City, the red soil mass excavated from a depth of seven 

 to ten feet was spread over part of a vegetable garden near 

 by and tomatoes,, beans and watermelons were planted on 

 it. The growth was even better than on the parts of the 

 old surface not covered, which had apparently become 

 somewhat exhausted by years of use. 



Examination has shown that the percentage of humus 

 or vegetable mold is less in the soils of the arid region, 

 but their humus contains more nitrogen. Thus, prob- 

 ably, on the average not only is the aggregate supply 

 of nitrogen in the soils of the arid region approximately 

 equal to that of humid soils, but its absorption by plants 

 is exceptionally favored by climatic conditions. 



As to the minerals which constitute fertility, the soils 

 of the arid region contain nearly fifteen times as much 

 lime, five times as much magnesia, three times as much 

 potash and about the same amount of phosphoric acid as 

 the soils of the humid regions. 



Significance of These facts. These leading characteris- 

 tics of California's horticultural soils are of the highest 

 significance to the vegetable grower because they show 

 that California is rich in soils of ideal excellence for his 

 purposes. They are light soils and therefore easy of cul- 

 tivation and not disposed to bake on drying; they are 

 deep, consequently well drained and yet absorptive and 

 retentive enough : they are exceptionally rich, consequently 

 extremely productive and durable and they can often be 

 given a new fertile surface by deep turning from the' fer- 

 tility of the greater depths. This was the natural en- 

 dowment which enabled the pioneer vegetable growers to 

 disturb the horticulaural peace of the world in 1849-50. 

 It remains to foster the achievements of later years and it 

 will endure definitely into the future. 



The distribution of these desirable soils gives all re- 



