Green Manuring. 



9 



length of their roots varied from 20 to 24 inches, the 

 crop was only equal to 6^ cwts. of grain per acre. 



Of the various leguminous plants tried by M. Schultz, the 

 roots of the blue lupins penetrated most deeply into the soil. 

 The white lupin came next in this respect, and slightly 

 surpassed the blue lupin in the fixation of nitrogen. The 

 yellow lupin was not quite so good as the other species of 

 lupin, while peas, though they exceeded the lupins in the 

 fixation of nitrogen, did not penetrate^the soil with their roots 

 more than from to 12 inches. The different varieties of 

 Lathyrus came next in value, and though they were not equal 

 to lupins they might be used instead of them. M. Grandeau is 

 himself experimenting with regard to green manuring in 

 France, and the results of his experiments will be looked for 

 with much interest. 



Records of experiments upon several Norwegian farms with 

 lupins and other nitrogen assimilating plants have been 

 recently published by Dr. Larsen.^ The principal subjects 

 of experiment were crops of potatoes and oats taken after lupins 

 ploughed in green in some cases, and in other cases har- 

 vested. The soil was of a poor sandy nature, and super- 

 phosphate, basic slag, and nitrate of potash were applied* 

 In most cases the whole crop of lupins was ploughed under, 

 but in one case it was harvested, and only the stubble and 

 roots ploughed under. The results were not so satisfactory 

 as in M. Schultz's experiments, and indicate that the crop of 

 lupins ploughed under was not able to supply sufiicient 

 nitrogen for the potato crop, as on several trial plots 

 -an increased amount of nitrate of potash added to the yield of 

 potatoes. 



Inoculation, or infection, was also tried by applying to each 

 acre of the land to be sown with lupins from 132 to 396 

 bushels of soil which had borne a crop of lupins. From 

 these experiments it is considered by Dr. Larsen that 264 

 bushels per acre of lupin-infected soil is sufficient to obtain 

 a good return of lupins, and that 132 bushels will often prove 



* Dyrkning af Lupin og nogle andre Kvcelstofsamlere af Forsogsleder Bastian 

 Larsen. Tidskrift for det norske Landbrug, 1896. Published at Christiania by 

 Grondahl and Sons. 



