1142 



Xotes on Manures for March. 



[Mar., 



applicable to farming practice. In laboratory experiments 

 muriates have sometimes done a certain amount of harm to 

 growing plants. These experiments, however, were not carried 

 out in soils, but under the rather artificial conditions of water or 

 sand cultures, and while the results are of scientific interest, 

 they cannot be directly applied to field conditions. Soil has a 

 great capacity for counteracting harmful effects, and it may 

 easily happen that a substance which is somewhat injurious in 

 the physiological experiment behaves quite differently in the 

 field. It is necessary, therefore, to approach the subject of 

 fertiliser value with a perfectly open mind. 



Since only one season's results are available it is not possible 

 to discuss them in any detail, but some interesting points stand 

 out. In the case of both muriate of ammonia and muriate of 

 potash no signs of harmful effects corresponding with the purely 

 laboratory experiments were seen so far as the writer is aware, 

 but there were cases when the yield from the muriate was less 

 than the yield from the sulphate, although there were also cases 

 where no difference was observed between them. 



The results seem to suggest that under some conditions 

 farmers could use either the muriate or the sulphate, whichever 

 they pleased, with a reasonable expectation of obtaining the 

 same return; but under other conditions the sulphate would be 

 safer. It is hoped that the experiments will be continued long 

 enough to allow us to say just w T hat are the conditions in which 

 the two manures act alike, and under what conditions prefer- 

 ence should be given to the sulphate. The writer would 

 appreciate any records from farmers who have had experience 

 with both types of fertilisers. 



Effect of the Manuring of Grassland on the Yield of Milk.— 

 An experiment made more than ten years ago at the Midland 

 Agricultural College, ana afterwards repeated at the Harper 

 Adams Agricultural College, deserves to be brought again to 

 the notice of dairy farmers, and might well be repeated as a 

 demonstration at other centres. Part of a pasture field was 

 dressed with fertiliser and part left unmanured : the plots were 

 completely fenced in and cow^s were grazed on them. At the 

 Midland Agricultural College the experiment was begun by 

 Mr. J. F. Blackshaw and continued for three years, records 

 being kept of the quantity and, over a considerable period, of 

 the composition of the milk. The fertiliser used was a single 

 dressing of 4 cwt. superphosphate and U cwt. sulphate of 

 potash per acre. The results when worked out as gallons of 

 milk per acre are as follows : — 



