94 



1924. 



The experiment was carried on for a second year, the green 

 crops, tares and mustard, being grown, but no further manurial 

 applications given. The green crops were sown on March 26th, 

 and were cut June 23rd, the weights, both green and dry, being 

 recorded. There is no occasion for dealing with these in detail, 

 but it may be said generally that the differences were not marked ; 

 what indications of increased crop were given bore, as with the 

 wheat of 1923, on the result of applying lime or a complete manure 

 including lime. 



3. The Relative Values of Lime and Chalk. 

 1923. 



In previous experiments on this subject the soil had not had 

 any applications given it beyond the lime and chalk respectively. 

 The experiment was therefore repeated, with the addition of 

 superphosphate and sulphate of potash, at the rates of 3 cwt. 

 and 1 cwt. per acre respectively. The soil used came, not from 

 Stackyard Field as usual, but from Lansome Field. The 40-lb. 

 pots were filled with soil, the whole of which was previously mixed 

 with lime or with chalk, so as to give the equivalent of 10 cwt., 

 1 ton, 2 tons, 3' tons and 4 tons of lime per acre. The super- 

 phosphate and sulphate of potash were added to the top 16 lb. of 

 soil used, wheat being sown on December 22rd. 



All the plants came up well. About the middle of March, 

 both lime, and to a lesser extent chalk, showed a clear improve- 

 ment over the control (unlimed) pots. In the case of the lime 

 applications the improvement was greater with the heavier dress- 

 ings. This held good until July, when the lime series showed a 

 progressive increase of crop up to 3 tons, but with 4 tons the crop 

 was shorter, though individual plants were greener and stronger. 

 With chalk, however, though there was a general increase over 

 the control, the heavier applications were not better than the 

 10 cwt. per acre. The crop was cut on August 13th, and the 

 following comparative results were obtained : — 



Lime and Chalk upon Wheat — Lansome Field Soil, 1 923. 



Corn 



Straw 



100 

 125 

 145 

 183 

 225 

 254 



128 

 135 

 132 

 129 

 141 



The weights are in close accordance with the appearances 

 already discussed, and with previous experiments made with the 



