FIELD EXPERIMENTS WITH FERTILIZERS. 1 43 



The diagram above will illustrate the method of laying out 

 the field, and the kinds and amounts of fertilizers per acre 

 applied on each plot. The soil of the experimental field is a 

 medium loam with a yellow clay subsoil, and has good natural 

 drainage. The field slopes slightly to the south, and the plots 

 are laid out with the long dimension corresponding to the slope, 

 in order to prevent the washing of soil from one plot to another. 

 The soil has not washed seriously, although very heavy rains 

 have caused some washing of the surface. In 1889, before the 

 experiment was begun, it was noticed that one side of the field 

 was more fertile than the other, and to overcome, as far as pos- 

 sible, the effect of this irregularity it was thought best to lay 

 out the field in two halves, the order of the plots on these to 

 be reversed. In this way 24 one-twenty-fourth acre plots were 

 laid out, as shown in the diagram of the field. In harvesting 

 the crop the yields on the corresponding plots of the two sets 

 are combined and are reported on the basis of one-twelfth acre 

 plots. 



Experiment with soy beans in ipoi. — The medium early green 

 soy bean was the crop grown in igoi. The data of the experi- 

 ment are given in Table 73, only the seed being taken into 

 account. 



The yields on the various plots without fertilizers were nearly 

 the same, indicating that the fertility of the soil is fairly uni- 

 form. Where the three ingredients, nitrogen, phosphoric acid 

 and potash, were used separately (plots A, B and C) the nitrate 

 of soda plot (A) gave slightly the best 3'ield. The results from 

 the use of the combinations of nitrogen and phosphoric acid, 

 nitrogen and potash, and phosphoric acid and potash, would 

 seem to show that the phosphoric acid was equall}^ as important 

 as nitrogen on this soil. Where all three of the fertilizers were 

 applied (plot G) there was very little increase in yield over 

 that obtained where only mineral fertilizers were used (plot F), 

 The results on the whole would seem to suggest that while the 

 nitrogen was possibly of some value to soy beans it should be 

 used more sparingly than for most crops, and especially more 

 so than for the cereals or grasses. 



It is interesting to notice that the yields obtained where 

 stable manure was used were quite a little larger than from the 

 plot supplied with a complete chemical fertilizer (G). This 



