STACK SILAGE MADE FROM BRACKENS. 213 



As compared with bracken silage, these samples are low in 

 albumen, but they are higher in carbohydrates and oily matters. 

 Whether the excess of these two constituents would be sufficient 

 to make up for the deficit in albumen it would require direct 

 experiments to prove. It seems probable that the bracken 

 hay would prove the superior fodder. 



EXPERIMENTAL STATIONS. 



PUMPHERSTON BARLEY CROP, 1887— UNEXHAUSTED FERTILITY 

 DERIVED FROM THE APPLICATION OF LIGHT MANURES. 



For the second time in succession a crop has been grown on 

 Pumpherston station without manure, in order to show the re- 

 lative amounts of residue left by the various manures applied 

 to the plots during two rotatioDS of four years each. The crop 

 grown without manure in 1886 was turnips, an account of which 

 is given in the previous volume of the Transactions, p. 237, 

 and in 1887 it was barley. The falling off in the turnip crop 

 was very great, and, judging from the weight of the crop, there 

 seemed to be a very small amount of plant food left as a residue 

 from the liberal manurings given in former years. The apparent 

 rapidity of the exhaustion was so great that it did not seem as 

 if there would be sufficient traces of former manures left to 

 materially affect the growth of the barley crop. It will be seen, 

 however, that the exhaustion has not been so rapid as the results 

 of the turnip crop led us to believe. It is evident, from the 

 figures contained in Table II., that the barley crop has 

 been able to make much better use of the manurial residues 

 than the turnips grown in the former year. The differences in 

 the amount of crop on the various plots is even more marked 

 than formerly, and it is certain that, if the season had not been 

 quite so dry, the differences would have been still more con- 

 spicuous. The results obtained with these two crops serve to 

 illustrate very well the chief defect of light manures when they 

 are exclusively relied upon for the growth of crops, especially 

 on soils that are a little stiff in their texture. They tend to 

 consolidate the soil, or at least they do nothing to open it up in 

 the way in which dung and other heavy manures do ; and thus 

 the roots of the young crop are retarded in their growth at the 

 stage when they are few and tender, and they therefore lose 

 time at the very season when it is most important that they 

 should rapidly establish their roots, so as to take full advantage 

 of the warm growing weather when it arrives. The season of 

 1886 was very favourable for the growth of turnips on land 

 fairly well supplied with moisture, as land is that has had dung 

 ploughed into it ; but on light dry land the crop was deficient 



