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TWENTY-NINTH FRUIT-GROWERS' CONVENTION. 



water being carried down by the Avater and deposited on the more com- 

 pact stratum of undisturbed soil. This beneficial action is due to this 

 hardpan being pierced by innumerable fibrous roots and the chemical 

 action of carbonic acid generated in their decomposition. 



If, then, we can at once grow nitrogen and humus, there remains to 

 be supplied only the two other principal elements — potash and phos- 

 phoric acid. Potash can best be supplied in the form of sulphate, 

 applying from seventy to one hundred pounds per acre immediately 

 before plowing. This will materially aid in the decomposition of the 

 green crop of herbage and also supply nourishment to the tree at a 

 time when most needed — during its growing period. For the other 

 element, apply superphosphate at the first irrigation in summer — from 

 five hundred to eight hundred pounds per acre. It must always be 

 borne in mind that a considerable part of the total percentage of phos- 

 phoric acid as shown by analysis will never be available for the use of 

 the trees. I am also of the opinion that lime, either as sulphate or in 

 its caustic form, can be applied with profit, especially for nut crops. 



Finally, keep up the supply of potash, phosphoric acid, nitrogen, and 

 humus, but first of all humus. 



FERTILIZATION. 



By S. M. WOODBRIDGE, of Los Axgeles. 



The knowledge of the world has been immensely augumented in the 

 last half century, and it is cause for regret that wisdom has not 

 increased proportionately. 



^ Our knowledge of pirates has enabled us to clear them from the high 

 seas, but our wisdom is not such as to keep a corresponding set of 

 robbers from the land, even within our own borders — witness the Ship- 

 building Trust and the U. S. Steel Corporation. 



Our knowledge in the matter of fertilization for many years has been 

 complete, but our wisdom has not been sufficient to enable us to take 

 advantage of the knowledge attained. Science has, decades ago, settled 

 the fact that of the fourteen or fifteen elements which go to make up 

 organic matter in plant growth there are only three expensive elements — 

 viz, nitrogen, phosphoric acid, and potash — in which any soil is likely 

 to be deficient. The changes which writers on the subject have 

 attempted to run in on these three elements, and the complications 

 with other matters that have been made with these three simples, are 

 in some cases amusing, but often serious, as they land the student in 

 the Slough of Despond. For example, the mixture of this subject with 

 treatment of soils and soil analyses. 



The treatment of any given soil is a subject entirely different and 

 apart from the subject of fertilization, although they are intimately 



