No 6. DEPARTMENT OF AGRICULTURE. 437 



The first three experiments deal with the influence of fertilizers, 

 and involve 10 treatments and G checks in each case. The next four 

 experiments deal with cultural methods and involve 12 treatments 

 in each case, except the last, which has six. The last four experi- 

 ments are a combination of portions of the first two types and deal 

 with both fertilizers and cultural methods.* As shown in the table, 

 the trees are of 10 varieties, though with one exception there are 

 two or more varieties in each experiment. In age at the present 

 time, the bearing trees range from 9 to 39 years ; and since the work 

 started they have produced over 1,315,000 lb. of fruit. 



In this one item of fruit, we may call attention to the facts that, 

 so far as American experiments are concerned, this amount is more 

 than treble that reported in any other single experiment, and very 

 distinctly more than the total fruit reported from all other similar 

 experiments combined. This does not mean that the importance of 

 the experiments elsewhere is to be minimized in the least, but it 

 should help to emphasize the fact that, in those cases where con- 

 clusions or attitudes are in conflict, very careful attention should 

 be given to the actual and relative amounts of evidence upon which 

 the differing attitudes are based. In fact, within our own experi- 

 ments we can find the counterparts of practically all those reported 

 elsewhere. If we had fewer experiments — for example, only one on 

 fertilization and another on cultural methods — our conclusions could 

 be much more easily formulated, and we might readily become ar- 

 dent partisans on either side of the questions, the side depending 

 merely upon which of the present locations our experiments chanced 

 to have. In other words, if we attempted to base our conclusions 

 upon any one or two of our present experiments, those conclusions 

 would be very diff'erent from any we would now formulate, on the 

 basis of all the results. There can be no doubt that when the whole 

 truth is known, we shall be able to account for all of the facts, and 

 this is what we are undertaking to do. 



THE INFIiUENCE OF FERTILIZATION 



The first factor to which we shall give attention is that of fertiliza- 

 tion. Can the yield, color, size and wood-growth^ of apples be in- 

 fluenced by fertilization, and, if so, how and under what conditions? 

 This has always been an important question, and five years ago, 

 when we were starting our experiments, we could find no data upon 

 which to base a definite, well-founded answer. We do not say that 

 we can fully answer it yet, but such progress as we have made 

 may be partially seen in Tables II and III. 



i. For further details, see our Bulletin 100 and our Annual Report for 1910-11. 



5. Quality is omitted from consideration at the present time, not because we do not con- 

 sider it important, but because as yet we have no measure of quality sufficiently accurate and 

 impersonal to enable us to make satisfactory comparisons of the fruit under different treat- 

 ments. 



