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THE MULCH. 



By O. W. BARRETT. 1 



Superintendent of Experimental Stations, Department 

 of Agriculture, Philippine Islands. 



THE motto of modern agronomists should 

 be, " Tilth, mulch, and microbes." The most 

 important of these may be microbes, but mulch 

 is a very big word, and one of the greatest 

 factors in plant economy. 



If there is one fundamental principle of 

 plant cultivation that is neglected more than 

 any other, it is unquestionably the artificial 

 protection of roots from heat and dryness 

 dangers. 



Tilth has to do with all the major opera- 

 tions of soil manipulation. Microbes, under 

 favourable conditions, attend to the oxidation, 

 nitrification, and other chemical transformations 

 which put crude organic substances into the 

 plant food form ; indirectly, with the acids 

 "set free" (sic) by the decomposition of 

 humus, and possibly by their own toxins and 

 excretory products, they are also concerned 

 with the ''breakdown" and solution of the 

 mineral elements themselves. 



1 Specially commissioned to investigate the Nectvia 

 disease in Trinidad (W.I.), and to report on the cacao 

 cultivation of that island in 1907. 



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