CEREAL CULTIVATION WESTERN AREA 391 



was $3 an acre more than the cost of maintaining a fallow 

 throughout the year, or $15 more in the 10 years, which 

 is considerably more than the value of the 14 bushels 

 of wheat at ordinary wheat prices. Moreover, there was 

 much winterkilling in this experiment which tends to 

 obliterate the advantages of a storage of soil moisture. 

 In August, 1910, after 7 years of the experiments had 

 elapsed, soil moisture determinations were made, when the 

 percentage of moisture found in each foot of soil to the 

 depth of 6 feet, in a fallowed and continuously cropped 

 plat, was as follows : - 



TABLE IX. PERCENTAGE OF MOISTURE IN EACH OF THE FIRST 

 6 FEET OF SOIL IN FALLOWED AND CONTINUOUSLY CROPPED 

 PLATS 



416. Summer tillage in California. Grain production 

 in California was originally continuous cropping, practiced 

 on as large an acreage as possible with a minimum cost. 

 The land became so weedy by this method, that summer 

 tillage was found to be necessary to clean the land. The 

 latter method has since become the regular practice, 

 but careless operations are so frequent that it can often 

 be more properly called summer fallow in the old sense. 



In the experiment at Modesto, already discussed (410), 



