il8 THE MONTHLY BULLETIN". 



Soil Ailments. 



Of course, every soil is likely to be destitute of the required amounts 

 of these necessary soil elements: humus, nitrogen, lime, potash and 

 phosphoric acid. Any deficiency of these can be supplied most cheaply 

 by the use of cover crops ; also by the use of stable fertilizer when that 

 can be had at a price that is not prohibitive. By such practice we also 

 secure the invaluable humus. There is no question but that our (Califor- 

 nia soils are laclcing in humus or decaying organic matter. The cover 

 crop supplies the need, and if a legume lilie vetch, Canadian field peas or 

 bur clover, furnishes nitrogen as well. 



Mr. Powell of New York, so famous as a producer of apples, contends 

 that he owes much of his success to tlie use of cover crops. Moreover, 

 he has by their use made many of his trees annual bearers. 



In the absence of stable manure we may use alfalfa, as suggested by 

 both Doctors Hilgard and Hopkins. Doctor Hilgard asserts that alfalfa 

 is worth $8.00 a ton simply to plough under as a fertilizer; Doctor 

 Hopkins suggested that it might pay well to grow alfalfa in fields 

 adjacent to the orchard to be used exclusively in fertilizing the soil. 



We maj^ also secure the separates directly from the dealers in com- 

 mercial fertilizers, and apply them as needed, or we may purchase a 

 complete fertilizer; the former practice is probably the better, if one is 

 willing to study into the matter thoroughl}'. For nitrogen, nitrate of 

 soda or Chili saltpeter is often used. Its ready solubility and quick 

 action makes it desirable in early spring before the ground warms up 

 and growth is active. The late Doctor King urged caution in its use, 

 as it may add to the amount of carbonate of soda or black alkali in the 

 soil and so do serious harm. This results from a chemical change in 

 the soil. The use of gypsum would lessen the danger. The ready 

 solubility of this salt makes its escape in the run-off jirobable, if not 

 used very cautiously. Many prefer tankage or dried blood. This 

 organic nitrogen is without objection ; it is all utilized. 



Limestone is becoming more and more recommended as a fertilizer. 

 It should be ground lime rock, not burnt lime. It is quite soluable and 

 so need not be very finely ground. 



For potash we may use potassium sulphate or potassium carbonate, 

 the chemical term for ashes. Though these are quite soluble, they are 

 retained in the soil, and, like the phosphates, are not usually lost by 

 drainage. They should be applied deep in the soil, where they are 

 needed and utilized. 



For the phosphates we may use finely ground bone or rock ; either is 

 excellent. If w^e wish to make these immediately available, we may treat 

 them with sulphuric acid, reducing them to superphosates, which are 

 more soluble. If, however, there is abundant humus in the soil the 

 untreated bone or rock, if very finely ground, and the bone steamed, 

 will be available and no whit lost. Phosphate slag is also available as a 

 source of the needed phosphates. 



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