EXPERIMENTAL STATIONS — BARLEY CROP, 1887. 225 



they owed their position to the presence of potash in the soil, 

 for plot 21, which for ten years had received no potash niamires 

 at all, has done just about as well. The good results obtained 

 on these plots must therefore be referred to the superphos- 

 phate, but especially to the nitrate of soda applied to each. Plot 

 22, Avhich got potash salts alone, produced the second worst 

 crop on the station — very little better than that borne by pl(it 

 27, which had been continually cropped without an)^ manure. 



There is a circumstance regarding the effect of potash manures 

 upon barley which deserves attention, though it is not appa- 

 rent on the chart, viz., the colour of the barley grain grown 

 with potash manures was distinctly darker than that which 

 received no potash. The grain on plot 21, that has never had 

 potash salts applied to it, is of a brighter colour, and altogether 

 of a more handsome appearance, such as to give it a preference 

 in the eye of a brewer. It would, therefore, seem to be advan- 

 tageous to apply no potash manures to barley that is grown for 

 malting. 



The guanos have not done well with the barley crop, and, 

 strange to say, the Peruvian guano is the worst. It gave the 

 best result when applied to potatoes the year before, so that a 

 smaller residue of that guano would be left for the barley. The 

 fish guano and Ichaboe guano contain their nitrogen in a less 

 soluble state than Peruvian guano, and on that account they 

 should not have been found so beneficial to the barley. It is 

 quite evident that the increase of grain on these plots, as in the 

 case of plots 15 and 16, cannot be due to the superior efficiency 

 of the manures immediately applied to them, but rather to the 

 residual nitrogenous matter afforded b}" the manures of former 

 years. As a class, the guanos are not well adapted for applica- 

 tion to cereals during a dry season, on account of the insoluble 

 condition of the greater proportion of their nitrogenous matter, 

 and the very poor appearance of these plots last year must be 

 ascribed to that peculiarity. 



The superphosphate plots, 28, 29, and 30 are a distinct 

 experiment. They had no superphosphate put on them for 

 the barley crop. The only manure applied was nitrate of 

 soda, which was spread in equal quantity over both halves of 

 these plots. The object in view in doing this was to get 

 some information regarding the amounts of unexhausted super- 

 phosphate applied in the one case the year before, and in 

 the other case two years before. The result is very instructive. 

 In the case of plot 28, there is not very much of the super- 

 phosphate that has come to the surface ; but as the manure^ 

 contained only one-third of its phosphate in the soluble 

 form, the deficiency on that plot must be ascribed to the coarser 

 condition of the phosphatic residues remaining in it. As 



VOL. XX. P 



