THE SOILS OF CALIFORNIA 33 



deeper and richer than any they had ever known else- 

 where and would grow grains, garden plants and 

 fruits-trees to a surprising size and abundance, but 

 that there were cases in which such results could not 

 be attained. Almost from the first there arose a de- 

 mand for scientific study of soils. After a few scat- 

 tering soil determinations by chemists whose chief 

 work was for miners and who accompanied their an- 

 alyses by such exposition of soil characters as they 

 could draw from European sources, a systematic and 

 exhaustive study of California soils was begun in 

 1875 by E. W. Hilgard, founder of the University 

 of California Experiment Station, and continued by 

 him and his successors for about forty years. This 

 undertaking not only placed California in the lead- 

 ership of all states in soil investigation and under- 

 standing, but it also resulted in an interpretation of 

 the relations of climates and soils both in formative 

 agencies and characters and in requirements of till- 

 age and cropping. This gave the work world-wide 

 significance in the contrasts which were made of soils 

 formed under humid and arid and semi-arid condi- 

 tions and the natural superiority of the latter when a 

 system of agriculture which provided irrigation and 

 tillage, as conditions might require either or both for 

 different classes of plants, is faithfully pursued. 

 Fortunately Dr. Hilgard lived to put his wide-reach- 

 ing results into generally available form. 1 



On April 1, 1900, in the latter part of the period 



1 Soils : Their Formation, Composition and Relations to Cli- 

 mate and Plant Growth, by E. W. Hilgard. The Macmillan 

 Company, New York, 1906. 



