CHAPTER XXV II. 

 VEGETABLE HUMUS. 



IN the chapter on animal manures I explained that humus 

 was the " product of complete putrefaction of animal or 

 vegetable refuse." " Vegetable humus," therefore, is 

 completely rotted vegetable matter. When the process 

 of putrefaction is complete there is left a black " fatty " 

 material, not very different from animal manure. In practice, 

 however, the material is dug in before the putrefaction is 

 complete, but it generally goes by the name of vegetable 

 humus or vegetable manure. 



For some years I have been carrying out experiments 

 with rotted vegetable matter, and at the time of writing 

 my latest experiment is just complete. Most of the trials 

 have been done in my vegetable garden, but some have 

 been made in the flower garden, and the results of these 

 may perhaps be of interest. 



The reasons for making the experiments were : (i) The 

 increasing difficulty in getting stable dung ; (2) To show 

 that humus is supplied to the soil by vegetable matter ; 

 and (3) To discover whether the humus contained in 

 rotted vegetable matter is as good as the humus supplied 

 in animal manure or to find a way of making it as good. 



I have been able to prove that humus is supplied by 

 vegetable refuse ; that it is very nearly the same as that 

 supplied by animal manure ; but up to the present I have 

 not discovered a method of treating it by which the results 

 obtained are quite as good as those obtained with animal 

 manure. It is very nearly but not absolutely the same, 

 so that it cannot be used alone for an indefinite period 



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