CARBONATE OF LIME. 



The most vital fact is one tliat we cannot now ex- 

 plain: the carbonate of lime makes the nitrifying 

 bacteria thrive. They cannot seem to exist with- 

 out it. Then it keeps the alfalfa in good health. 

 Why should alfalfa ot any other plant become sick"? 

 "We think we know that plants give off certain toxic 

 principles, poisonous to themselves. That is, the 

 alfalfa roots exhale perhaps a poison that is in- 

 jurious to itself and to other alfalfa roots. When 

 there is much carbonate of lime in the soil this 

 poisonousi principle is in some way neutralized. Thus 

 the alfalfa keeps in health and vigor and goes right 

 on performing its miracles. This helps explain 

 some things that have puzzled the wisest of us. 

 Many men have had good, vigorous stands of alfalfa 

 well fed with mineral fertilizers and with stable 

 manures, and all at once with no warning whatever 

 it would all die as though stricken with plague. This 

 has happened repeatedly in many eastern and south- 

 ern states. Never, so far as the writer has been able 

 to learn, has it happened where the alfalfa was 

 growing on a soil even fairly well supplied with 

 carbonate of lime. 



Carbonate of lime, we may as well fairly confess, 

 is 'the very keynote of successful alfalfa culture. 

 Drainage and carbonate of lime are the two essen- 



(107) 



