1910.] Summary of Agricultural Experiments. 147 



1908. By omitting in turn nitrogen, phosphoric acid, and potash from 

 a complete dressing, phosphoric acid was shown, as in the previous 

 five years, to be the constituent most required by the soil. 



Calcium cyanamide and nitrate of lime were compared with sulphate 

 of ammonia, quantities of each containing the same amount of nitrogen 

 being applied. Both the new manures yielded slightly smaller results 

 than sulphate of ammonia, but the differences were so small as to be 

 within the range of experimental error in most cases, and therefore the 

 manures appear to be equally useful in the production of turnips, and 

 which of them should be used can be decided by the price per unit of 

 nitrogen. 



In a trial of the most profitable quantity of superphosphate, the 

 results of 1907 were confirmed. Both with and without dung 6 cwt. 

 of superphosphate gave a larger crop than 3 cwt., but the value of the 

 increase did not cover the greater cost of the manuring ; 9 cwt. produced 

 a diminution in the crop. The larger quantities might be profitable at 

 the end of the rotation, on account of their residual values, but apart 

 from this, 3 or 4 cwt. of superphosphate appears to be the limit of 

 profitable application so far as the turnip crop is concerned. 



High and low grade basic slag were compared on two plots. The 

 same quantity of phosphoric acid was applied per acre, and the results 

 were almost identical. 5! cwt. per acre of the high grade slag was 

 used, at a cost of 335. yd., and as the quantity of low grade slag 

 (11^ cwt.) necessary to supply the same amount of phosphoric acid cost 

 405. gd., the profit due to the use of the high grade slag was 45. greater. 



The practice of applying a few cwt. of superphosphate, as the only 

 artificial fertiliser along with dung, is not uncommon. A comparison 

 of the plots, however, showed how much more profitable is a complete 

 or balanced manure when no dung is used, and when dung is applied 

 it is still necessary to supplement the superphosphate with nitrogen and 

 potash if a full crop is to be obtained. 



Manuring of Swedes (Midland Agric. and Dairy Coll., Bull. 4, 

 1909-10).- — These trials have now been carried out for six years and 

 will be continued in 19 10. In 1909 ten loads of farmyard manure per 

 acre gave an increase over the unmanured plot of 4 tons i6f cwt. per 

 acre, and fifteen loads farmyard manure an increase of 6 tons 1 cwt. 

 Ten loads supplemented by the following dressing of artificials : — 

 Sulphate of ammonia, 75 lb. ; superphosphate, 250 lb. ; sulphate of 

 potash, 30 lb., produced an increase in yield over the unmanured plot 

 of 7 tons 8^ cwt., at a cost for the artificials of 16s. 6d. per acre. The 

 most profitable form of manuring was by artificials alone. Double the 

 quantities already mentioned were applied, at a cost of 335. per acre. 

 The increase in the crop amounted to 8 tons 19J cwt., which, valued at 

 io5. per ton, gives a profit of 56s. jd. per acre. In the last six years 

 the profit from this dressing has been on the average 405. 6d. per acre. 



Sulphate of ammonia has been compared with nitrate of soda in a 

 complete dressing, and the former has proved more profitable, the 

 average difference in profit in six years being 35. 3d. Superphosphate 

 has given a considerably larger annual profit than basic slag, dissolved 

 bones, or bone meal. As a source of potash sulphate of potash has 

 given better results than either muriate of potash or kainit. 



Manuring of Swedes (Cumberland and Westmorland Farm School, 



