1920.] 



Notes on Manures. 



an effective fertiliser which could be easily applied instead of 

 the less valuable waste product. 



Comparison between home-mixed and purchased Compound 

 Fertiliser. — In the Notes for December (this Journal, November, 

 191 9) reference was made to a compound fertiliser offered at 

 per ton, and a home-made mixture was suggested which 

 would give the same amount of fertiUsing constituents at a 

 considerably lower price. This has led to correspondence 

 with some of the fertiliser manufacturers, who felt that the 

 composition stated did not fairly meet the case, and one of 

 the manufacturers made the entirely valid point that the mix- 

 ture proposed in these Notes was based on the salesman's 

 ammonia figures, whereas in a court of law the salesman would 

 probably have been held to his nitrogen figure which was 

 somewhat higher. Working on this basis it would be necessary 

 to add sufficient sulphate of ammonia to increase the nitrogen 

 by 0*7 per cent., which would increase the cost of the home- 

 made mixture by 15s. per ton. Even after allowing for 

 this increase in value, however, the figure of £19 per ton 

 remains unjustifiable on a purely cost basis. We have every 

 desire to be fair to the fertiUser manufacturers, and the 

 sole purpose of the note was to draw attention to the price, 

 which is admittedly in excess of what a -first-class manu- 

 facturer would charge. 



Growth of Swedes where the Supply of Farmyard Manure Is 

 limited. — A Lancashire correspondent asks what fertiliser he 

 could use for swedes in the following conditions : — (i) He has 

 not much farmyard manure ; and (2) Swedes do so well on 

 one field that he is anxious to grow them there again if he can. 



Numerous experiments on the manuring of swedes which 

 have been carried out by Professors Somerville and Gilchrist 

 and others in the north of England have shown that it is un- 

 necessary, as a rule, to use both farmyard manure and arti- 

 ficials for swede crops. 



It is well known that good results can be obtained with 

 farmyard manure, but where insufficient is available to allow 

 of suitable dressings, good results can be obtained with 4 to 

 6 cwt. of superphosphate or basic slag, together with i cwt, 

 sulphate of ammonia, at the time of sowing, then i cwt. nitrate 

 of soda as a top dressing at the time of singling. 



With reference to the question as to whether swedes can be 

 sown on the same land year after year, the chief trouble is in 

 regard to the flea beetle ; provided this pest is absent there is 

 no particular difficulty in growing successive crops of swedes. 



4 K 2 



