1909.] Summary of Agricultural Experiments. 407 



of lime were viewed side by side, the plot which had received nitrate 

 of lime looked darkest in colour and most vigorous in growth. This 

 appearance was confirmed when the crops were weighed. 



Foreign and Colonial Experiments. 



Manuring of Barley (Deutsche Land. Presse, Nos. 27 and 28, 1909). — 

 In these publications, Prof. Julius Stoklasa, Director of the Chemical 

 Experimental Station at Prague, gives the result of some recent in- 

 vestigations into the manuring of barley for brewing purposes. 



He shows that the food requirements of the plant vary very con- 

 siderably during its period of growth, and are at their maximum during 

 the second month. The quantities of nitrogen, phosphoric acid, and 

 potash assimilated per acre are given as follows : — 



During 



During 



During 



During 



30 days 



60 days 



90 days 



1 20 days 



of growth. 



of growth. 



of growth. 



of growth. 



lb. 



lb. 



lb. 



lb. 



3 9 



766 



82-1 



83-9 



I'l 



19-8 



33*9 



357 



3-8 



94-6 



1 io'6 



114-2 



Nitrogen 

 Phosphoric acid 

 Potash 



It would seem from this that the bulk of the nitrogen, 55 per cent, 

 of the phosphoric acid, and 83 per cent, of the potash, are taken from 

 the soil during the first sixty days of the plant's growth, from which 

 it may be inferred how important it is that these manurial substances 

 should be present in an easily available form. 



Prof. Stoklasa shows also that the assimilative capacity of the roots 

 of barley is less than that of wheat, oats, or rye, though, on the other 

 hand, when there is an absence of food materials in the soil, the roots 

 of barley develop to an abnormal extent, and penetrate downwards into 

 the soil searching for food. 



Owing to the short period of growth, the object of the farmer must 

 be to provide the necessary manurial constituents in an available form 

 during the first two months. As will be seen from the above table, 

 potash is required in the largest quantity, then nitrogen, and then phos- 

 phoric acid, and when growing barley for brewing purposes these must 

 be given in such a way as not to injure the quality or the capacity for 

 early ripening. 



Experiments have shown that the addition of nitrate of soda, super- 

 phosphate, and muriate of potash to land which has been well manured 

 with nitrate of soda for "the preceding crop of sugar-beet results in a 

 better yield than if phosphates and potash alone had been applied. The 

 following table shows the comparative results : — 



Cwts. per acre. 



Per cent. 



Manures applied. 



1. Unmanured 



2. 180 lb. 40 per cent, muriate of potash, 



180 lb. superphosphate (17*5 per 

 cent, soluble) 



3. 180 lb. muriate of potash, 180 lb. 



superphosphate (17-5 per cent, solu- 

 ble), 90 lb. nitrate of soda (15*6 per 

 cent. nitrogen)... 



Grain. 

 1 1 -8 



Straw. 

 16-6 



>4/9 



Starch. 

 64 '5 



66-8 



66 -o 



Nitrogen. 

 12-07 



10-5 



