CHAPTER VII 



BACTERIZED PEAT: ITS PREPARATION AND GENERAL 

 PROPERTIES 



Need for a mixed culture Why peat was used as a medium 

 Other possible media Decomposition of peat by aerobic 

 bacteria Superiority of artificial over natural methods 

 Effects of decomposition A simple experiment Treated 

 peat contains fifty times as much plant food as stable 

 manure Peat the ideal medium The aerobic bacteria 

 Sterilizing the peat Bacillus radicicola, Clostridium pas-- 

 teurianum, and Azotobacter Conditions of growth Symbi- 

 otic relationships Inoculating the peat Why the soil 

 should benefit Effect of nitrogen fixation Influence on 

 phosphates and potash Accessory food bodies Claims 

 advanced on behalf of humogen. 



A CONCLUSION of supreme importance was reached 

 as a result of the experiments made in the Botanical 

 Laboratories of King's College on Bacillus radicicola, 

 the micro-organism responsible for the fixation of 

 nitrogen in connection with leguminous plants. The 

 discovery had been made that the bacillus, when 

 mixed with soil and dried, was able to retain its 

 vitality unimpaired certainly for a considerable 

 number of months, and in favourable conditions for 

 at least as long as three years. Unquestionably 

 soil, for the introduction of the bacillus, was a 

 medium vastly superior to the cotton used in 

 America. In a previous chapter I have attempted 



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