I04 Journal of Agricultural Research voi. xxii. No. a 



During the growth of the plants the inoculated series showed greater 

 development, which is apparent upon examining the dry weights. 

 Cultures i and 2 of the inoculated series show no effects from lack of 

 sulphates, and all the sulphur-fertilized pots contained numerous well- 

 developed nodules. 



The total nitrogen insoluble in acetic acid was no greater in some 

 of the cultures receiving added sulphates than in the controls, so no 

 statement can be made that sulphate addition caused this fraction to 

 become larger. The nitrogen content of the fraction soluble in acetic 

 acid is lower in i and 2 of the uninoculated series. The increase in 

 percentage of sulphur caused by fertilizer treatment is accounted for 

 generally by higher sulphate content. Although the organic sulphur 

 is apparently higher in some, the results are not consistent with the total 

 sulphur, to state that the former results from increased sulphur assimi- 

 lation in this experiment. Total sulphur in the acetic-acid extracts 

 runs parallel with sulphate sulphur results and is slightly higher, showing 

 that there is some sulphur in the organic form not accounted for in the 

 precipitate from acetic-acid solution. This was also found to be true 

 with clover grown in other pots which was harvested while in blossom. 



The ratio in weight of tops to roots is greater in the inoculated sulphur- 

 fertilized cultures than in the uninoculated sulphur-fertilized cultures. 

 This difference does not appear to be due to inoculation alone, for this 

 does not hold true in comparing i and 2 of both series, while the ratio of 

 tops to roots in i and 2 of the uninoculated series is greater than the 

 remaining four where there is heavy nodule growth. Amy and 

 Thatcher (/) report a greater ratio in weight of tops to roots where 

 inoculation was made with alfalfa and sweet clover. 



The sulphur content of the roots is larger than in the other portion 

 of the plant, whereas the opposite is true in percentage of nitrogen. 



The second part of this work was carried on with beaverdam soil and 

 red clover. Each pot contained 7 kgm. of soil, and the following amount 

 of fertilizers were added as indicated in Table II: 12 gm. of calcium 

 sulphate, 10 gm. of sodium sulphate, 2 gm. of sulphur, and 6 gm. of 

 sodium nitrate. Two gm. of potassium chlorid and 10 gm. of calcium 

 carbonate were added to all the soil cultures. Twenty red clover plants 

 were allowed to grow in each pot, and the moisture content was kept at 

 40 per cent. The first crop grew at the same time as the clover on the 

 Medford loam soil and was also cut before the blossoming stage. Three 

 other crops were grown on these same cultures. The first was harvested 

 on March 24, the second on May 20, the third on July 9, and the fourth 

 on August 17. The last three crops were cut during the blossoming stage. 

 The results are given in Table II. 



