THE ORANGE IN CALIFORNIA FERTILIZATION. 143 



determine what ingredient or ingredients are most urgently 

 required to restore production. 



A. simple leaching with water shows many of our valley 

 soils to contain, in water-soluble condition, a large proportion 

 of potash salts, so as to render the idea of supplying more of 

 the same substance simply absurd. Thus, the ten-acre experi- 

 mental tract near Chino contains per acre an average of over 

 1,200 pounds of water-soluble potash in the first three feet, 

 equivalent to the amount required for eight twenty-ton crops 

 of sugar beets, without drawing on the less soluble but much 

 more copious soil store. Similar cases are common in other 

 valley regions of the State. These facts speak for themselves. 



Equally simple tests show that in the great majority, proba- 

 bly at least three fourths, of the soils of the State, lime is so 

 abundant that it need not be supplied for centuries to come at 

 least. These facts are easily ascertainable by any one having 

 even a superficial knowledge of chemistry. 



But more elaborate investigation and analysis show that 

 while both lime and potash are present in unusually large pro- 

 portion, as compared with soils east of the Mississippi and in 

 Europe, phosphoric acid and nitrogen are, on the contrary, as 

 a rule, present in small amounts, and likely to become defi- 

 cient in a short time under exhaustive cultivation. 



What to Use First. Upon these plain and simple facts is 

 based my recommendation to California farmers that, when- 

 ever production of their land becomes unsatisfactory, they 

 should try any large-scale fertilizer first with phosphates and 

 nitrogen, and, should this not prove fully satisfactory, then 

 with potash also; this being the order in which these substances 

 are likely to become deficient in most of our soils under culti- 

 vation. 



In the course of time potash fertilization will become widely 

 necessary in this State, also; but it is certainly not among the 

 first things generally required, as is actually the case in the East 

 and in Europe. Under continuous heavy cropping with root 

 crops, such as beets, potatoes, or artichokes, or with small fruits, 

 such as strawberries, potash fertilization has already, as a mat- 

 ter of fact, become necessary at some points and will gradually 

 become more so. On the gray soils of the foothills of Amador 

 and Placer counties we have found it necessary from the very 



