1922.] 



Notes on Manures for March. 



1143 



Yield on unmanured Yield on manured Increased yield 



plot. plot. due to manure. 



gal. per acre. gal. per acre. gal. per acre. 

 1st year ... 136 220 84 

 2nd year ... 164 250 86 

 3rd year ... 137 218 81 



In the fourth year the increased yield was 119 gal. per acre. 



Even at the pre-war price of milk (6d. per gal.) the whole 

 cost of the manure w^as paid off in the first year, and there 

 was a balance on the farmers' side, while the whole of the 

 increased yields in the 2nd and 3rd years were clear profit. 



Analyses of the milk by Mr. Golding showed, as the result 

 of manuring, a large increase in the total amount of butter 

 fat, but a slight falling off in the percentage, and no appreciable 

 change in the percentage of other constituents of the milk, 

 though of course an increase in the total amounts. 



The Harper Adams experiments were on slightly different 

 lines, there being three plots — one unmanured, one receiving 

 superphosphate only (2J cwt. per acre), and the third receiving 

 superphosphate (2J cwt. per acre) and potash (J cwt. sulphate 

 of potash per acre). The average yields of milk for the three 

 years summer grazing (20 weeks) were : — 



Yield on unmanured Yield from superphosphate Yield from superphosphate, 

 plot. only. + potash. 



gal. per acre. gal. per acre. gal. per acre. 



175 208 212 



Again a distinctly profitable increase from the use of 



fertilisers.* 



Use of Lime on Corn Crops in which Clover is to be Sown. — 



A correspondent raises the question whether lime should be 

 applied to a corn crop in wilich clover is to be sowm, w T hen 

 there is reason to expect a deficiency of lime in the soil. This 

 should certainly be done. Cases are constantly being brought 

 to the writer's notice of failure of clover, either in patches or 

 over a large part of the field, owing to shortage of lime. 

 Typical instances are as follows : — 



Herts. Suffolk. Norfolk. 

 On the good parts ... 0*2 0*8 0'6 per cent, of calcium carbonate 



On the bad patches ... 0'01 0'07 0'2 „ „ .. „ 



The correspondent further asks whether hydrate of lime 



would be a suitable substance for the purpose. It would. He 



should, however, obtain quotations for ground limestone, which 



w T ould also be suitable : it is too late now for quicklime. In 



comparing prices it should be remembered that 100 lb. of ground 



limestone has the same effect as 74 lb. of hydrate of lime, and 



therefore it should be correspondingly cheaper. 



* The results of these experiments are also discussed together with those 

 obtained in experiments in Ireland in Miscellaneous Publication No. 30, 

 pp. 6, 7, 8, 19, 20, 21. 



