1905.] 



Green Manuring. 



The value of green manuring as a means of improving the soil 

 has been recognised from early times, but it is only in recent years 



periments conducted by M. Schultz, at Lupitz, in Saxony, over 

 a period of forty years, showed conclusively the value of the 

 method for the improvement of light, sandy soil. The basis 

 of this system was the (1) cultivation of leguminous plants, 

 notably lupins, in alternation with cereals, potatoes, and other 

 crops ; and (2) the use of lime, potash, and phosphoric acid, 

 without any nitrogenous manures. The method was followed 

 on the whole of the Lupitz estate of 600 acres, and in 1 891 the 

 result of the experiment was described by M. Schultz in the 

 following words : — " With a limited stock of fatting cattle, 

 without buying any nitrogenous manures, by adding potash, 

 phosphoric acid, and lime, I have succeeded in fixing, at the 

 expense of the atmosphere, a considerable quantity of nitrogen, 

 by which I have been enabled to diminish by 50 per cent 

 the expense of the production of cereals grown at Lupitz ; or, 

 which comes to the same thing, to raise the average profit to 

 30s. per acre, notwithstanding the unfavourable state of the 

 markets." 



The advantages of green manuring, so strikingly illustrated 

 by the success of the Lupitz method, are due to the fact that 

 the leguminous plants used for green manuring supply the soil 

 with nitrogen in an easily available form for the use of the 

 following crop. Like the straw in farmyard manure, they enrich 

 the soil in humus., and on porous soils and in dry weather this 

 decaying humus is valuable as a means of retaining moisture. 

 The deep-rooted plants which are frequently employed draw up 

 a supply of mineral food from the subsoil, and thus enrich the 

 surface soil, while they help to open up the subsoil for the 

 succeeding crop. The essential factor of the Lupitz system 

 is the substitution of leguminous plants, possessing the power 

 of gathering nitrogen from the air, for farmyard manure The 

 plants to be selected for green manuring should, therefore,, 

 be leguminous, i.e., peas, beans, vetches, lupins, serradella,. 

 clovers, &c, if it is intended to employ green manuring as 

 a cheap substitute for farmyard manure. Non-leguminous 



Green Manuring 1 . 



that scientific investigations have been made 

 into the conditions connected with it. Ex- 



