28 



ARTIFICIAL MANURES 



[CH. 



Increases, but on a smaller scale, have also been observed by 

 Greig in some of the Aberdeen experiments on turnips 1 : 



Per acre 

 tons cwts 

 Sulphate of ammonia (f cwt), sulphate of potash (1 cwt) + 2J cwts 



superphosphate ... ... ... ... ... ... " ... 15 18 



Sulphate of ammonia (f cwt), sulphate of potash (1 cwt) + 5 cwts 



superphosphate ... ... ... ... ... ... ... 17 8 



Sulphate of ammonia ( cwt), sulphate of potash (1 cwt) + 10 cwts 



superphosphate ... ... ... ... ... ... ... 18 7 



Basic slag. This fertiliser is not quite so soluble as super- 

 phosphate, but on the other hand it contains more free lime. It 

 is particularly associated with grass land, and is dealt with from 

 that point of view in Chapter v. But it is also useful on arable land 

 and has given good results for leguminous crops, and for swedes 

 and turnips, especially where finger and toe is common. In the 

 Irish experiments it gave approximately the same results as 

 superphosphate, both for turnips and for hay 2 : 



Average yield of turnips per acre, 5 years, 1908-12. 



Yield of hay (1912 and 1913). 



In the Glasgow experiments 3 basic slag gave smaller crops of 

 turnips than superphosphate, but the feeding value, as shown by 



1 Aberdeen Bull. No. 10. 



2 Journ. Dept. Agric., Ireland, 1914, 14, pp. 295 (turnips) and 259 (hay). 

 8 West of Scotland Agric. Coll. Bulls. Nos. 15 and 23. 



