10 April, 1918.] 



Wheat Manuiial Trials 



225 



These tables bring out the striking efficacy of superphosphate as a 

 manure on our Australian wheat lands. At Rutherglen, as compared 

 with the no manure plot, 1 cwt. superphosphate per acre produced an 

 additional yield of wheat worth 28s. 9^d. per acre (wheat at 4s. a 

 bushel) and returned a net profit (after deducting the cost of the manure) 

 of 23s. 9id. per acre as a direct result of using the manure. Calculating 

 on a similar basis, ^ cwt. superphosphate jDroduced a net profit of 20s. 

 3^d. per acre. From this it will be seen that by using the heavier 

 dressing the grower was able to obtain 3s. 6d. per acre, or practically 

 an extra bushel of wheat per acre, for nothing except perhaps the trouble 

 of setting the drill to sow at the heavier rate. 



Heavy a^^d Ligjit Dressings of Superphosphate at Rutherglen 

 — Five Years^ Results. 



Treatment. 



No Manure 

 Bonedust 

 Basic Slag 

 Super. \ cwt. 

 Super. 1 cwt. 

 Super. 2 cwt. 



Yield 

 per acre. 



bushels. 

 8-6 

 12-7 

 13-5 

 14-3 

 15-8 

 15 -9 



Increase 



per acre 



over 



no manure. 



bushels 

 per acre. 



4-1 



4-9 



7-3 



Value of 

 increase 



at 4s. 

 bushel. 



16 

 19 



28 

 29 



5 



7 



9Jr 



Cost of 

 manure, 

 per acre. 



S. d. 



2 6 



5 



10 



Net profit 



per acre 



after deducting 



cost of 



manure. 



s. d. 



20 3.V 

 23 9| 

 19 2 



Note. — The e.vpense of putting in each plot is the same except so far as the manures are concerned. 

 3975.-2 



