242 



Journal of Agricultural Research 



was added to the complete fertilizer may have been due, as suggested 

 for the previous crops, to a depressing effect of an excess of soluble salts. 

 The favorable effects of calcium sulphate were most decided. 



Summarizing the results obtained with the leguminous plants, it may- 

 be stated that sulphates added to this soil were decidedly beneficial to 

 the growth of the crops so far investigated. With the large-seeded bean 

 and pea the effects are practically confined to the increased seed develop- 

 ment. With the hay crop, however, the results are favorable to the 

 growth of the straw portion of the plant. Calcium sulphate in general 

 is considerably superior to sodium sulphate in its fertilizing action. In 

 the case of clover both of these compounds, when added separately, 

 increased the root development markedly. This would tend to increase 

 the feeding power of the plant and may largely account for the increase 

 of hay produced by their use. Sulphur alone depresses the general 

 development of the plant, with the apparent exception of the clover roots. 



CRUCIFERAE 



Radishes (Raphanus sativus). — The variety grown was Earliest Scarlet 

 Turnip. Crop A followed two crops of rape on the same soil, both of 

 which had been fertilized. Crop A was not fertilized. Crop B followed 

 crop A on the same soil and was not fertilized. Crop C was also grown on 

 the same soils, but was fertilized. Fifty days from planting crop A, 

 alternate rows of the crop were harvested from one set of boxes for photo- 

 graphing. These were dried and the weights recorded. The remaining 

 plants were allowed to develop seed and the residue rejected. Plate 

 XX, figure 2, is therefore the only available comparison covering the 

 whole crop. The air-dried yields are given in Table IV. (See Pi. XX, 



%-3-) 



Table IV. — Average weights (in grams) of air-dried radish crops 



1. Control 



2 . Complete fertilizer 



3. Complete fertilizer-1-sodium sulphate 



4. Complete fertilizer-f calcium sulphate 



5. Sodium sulphate only 



6. Calcium sulphate only 



7. Sulphur only 



.S 



2-5 



4-7 

 4-7 

 7.0 



5-0 



4-7 

 3-7 



Crop B 

 (whole 

 plants). 



19.9 

 36.5 



30-5 

 2S.4 

 24-3 



CropC 



( whole 

 plants). 



34-9 

 48. o 

 47.6 

 10. 9 

 "•3 



Average 

 relative 

 yields of 



whole 

 plants for 

 all crops. 



100 

 236 

 256 



257 

 126 



IIS 



60 



The results call for special comment. They show, especially where 

 freshly fertilized (crop C), an unmistakable stimulus to growth by sul- 

 phates. The effect is much more pronounced where the sulphates were 

 applied alone than where the complete-fertilizer ration was used. A 



