Organic Manures 



Green Manure. 



Green manure can be divided into two categories, 

 non-leguminous and leguminous. The non-legumi- 

 nous are more often sown as catch-crops after wheat. 

 They only collect the nitrates formed in the soil 

 at the end of the season, which would otherwise 

 be washed away. The other manures necessary to 

 their development they evidently draw from the 

 soil. Their utility, therefore, lies in conserving the 

 nitrogen, but they also play an important part in 

 adding humus to the soil and thereby making a 

 good crop possible where the results otherwise 

 would be mediocre. 



As non-leguminous green manure turnips or 

 mustard or rape are usually chosen, but spurry, rye, 

 and buckwheat are also used. It is much better 

 to have a non-leguminous green manure than 

 none at all, but recourse to leguminosa is infinitely 

 to be preferred. WTiile capturing the nitrate formed 

 in the soil, they also take possession, by means of 

 bacteria located in the nodules of their roots, of 

 the free nitrogen of the air and assimilate it, thus 

 accumulating in the stem and the roots of the plants 

 a quantity of nitrogen which is the most valuable 

 manure, and by far the most expensive in agricultural 



use. 



Other deep-rooting green manures fetch up the 

 phosphoric acid and potash from the subsoil. These 

 accumulate in every part of the plant, and when 

 ploughed in are at the disposal of the next crop and 

 much nearer the surface, and so placed that the roots 

 can draw on them abundantly. 



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