THE SOILS OF CALIFORNIA 41 



"The soils of California taken as a whole are ex- 

 ceedingly productive. They may be compared to the 

 rich bottom lands of the humid regions. The un- 

 favorable conditions that may exist, such as hardpan, 

 alkali, poor drainage, poor structure, etc., can be 

 readily recognized; but a superficial examination of 

 the soil is not enough. Soils should be examined to a 

 depth of at least six feet, bearing in mind that plants 

 that would in a humid region send their roots two 

 or three feet into the soil, are advantaged in Cali- 

 fornia by having a root penetration of six to twelve 

 or more feet." 



The reader may perhaps be assisted to a fuller 

 realization of the unique characters of California soils 

 and their diversity within exceedingly narrow limits 

 by considering the foregoing carefully drawn details 

 of their occurrence in connection with the references 

 to topography in Chapter I. Let him remember that 

 above the timber line he may stand upon many peaks 

 and ridges of perfectly bare granite and look down 

 upon valleys, fifty miles away and ten to fourteen 

 thousand feet below, in parts of which borings of two 

 or three thousand feet through the soil mass have not 

 reached bed-rock. With such extremes within sight 

 it is perhaps easier to realize the diversity at vari- 

 ous elevations and inclinations between them. 



Determination of the adaptations and capabilities 

 of California soils by the pioneers through their in- 

 troduction and 'trial of plants from all parts of the 

 earth, followed by definite understanding of general 

 and local soil characters and qualities resulting from 



