May 26, 1916] 



SCIENCE 



735 



I can not refrain from prolonging this 

 part of the discussion by saying that in- 

 vestigational work may be the most prac- 

 tical kind of activity that men may engage 

 in. To cite a field of inquiry in which I 

 may claim more or less acquaintance, I may 

 say that the problem of the rest period of 

 plants — while an investigation seeming on 

 its face to serve no practical purpose, has 

 already been found to shed light on the 

 very live and very practical question of 

 hardiness of fruits in cold climates. And 

 in warm climates, particularly under semi- 

 arid conditions, I am convinced that it 

 will eventually serve as a foundation stone 

 on which to establish irrigation and prun- 

 ing practises as applied to deciduous fruit 

 trees. Both pomologieal and irrigation di- 

 visions are now carrying on experiments, 

 independently and cooperatively, to deter- 

 mine these things, but I greatly fear that 

 all present efforts are only scratching the 

 surface of the one great question of orchard 

 fruitfulness. 



But I have wandered away from my sub- 

 ject as I had meant to discuss it. What I 

 started out to say was that we need more 

 facts pertaining to horticultural questions. 

 Not only should more problems be investi- 

 gated in an experimental way, but when- 

 ever a piece of work is carried out, no mat- 

 ter how small it may be, should we not bend 

 every energy toward establishing each and 

 every step so securely that all will endure 

 the wear and tear of the multitude of other 

 workers who may desire to climb toward 

 other things over the secure stones that we 

 have laid? Let us not despise experiments 

 with commonplace things just because 

 others have been content to pass them by 

 on the strength of current statements (un- 

 supported by experimental proof of any 

 kind) which say that it is best — yea even 

 vitally necessary — to do thus and so, if cer- 

 tain results are to be attained. 



I wish I had time to submit a full list of 

 the common things teachers of horticulture 

 have to discuss without being able to offer 

 evidence that would pass muster in a jus- 

 tice's court. However, I shall have to be 

 content with a few random shots that occur 

 to me on the spur of the moment : In graft- 

 age what is meant by an uncongenial stock 

 or lack of affinity between scion and stock? 

 What happens when a bud with its adhering 

 piece of bark is inserted beneath the bark of 

 a stock? Does each part possess a complete 

 cambium layer or each only half a layer? 

 In healing wounds how are two outer bark 

 surfaces, upon meeting, enabled to grow to- 

 gether? What relation does callusing bear 

 to root formation in cuttings? Where can 

 we find some reliable quantitative compari- 

 sons of tops and root systems of fruit trees ? 

 How does branch pruning affect the root 

 system of trees? Is there a corresponding 

 root for each vigorous new water sprout? 

 What do we really know about the secret 

 of fruitfulness in trees, particularly the 

 fruiting habit? Why do so many apple 

 trees bear on alternate years? Why can 

 not Ben Davis and Baldwin, for example, 

 be made to bear annually? Why is it an 

 apple tree may bear fruit buds enough for 

 a "full" bloom and only ten per cent, 

 really open in spring? What is the true 

 effect of sunlight on fruit bud formation? 

 What are the causes of growth periodicity 

 in trees and the relation of same, if any, to 

 fruit-bud formation? What is "hardi- 

 ness" in trees and buds? What is the n.a- 

 ture and cause of coloring in apples? 

 What do we know about the value of select- 

 ing buds in deciduous trees? Is "pedi- 

 gree ' ' in trees a humbug ? Why do certain 

 individual trees appear to have a superior 

 record for fruitfulness? What is meant by 

 vigor in trees? What is the true cause of 

 "June drop" in fruit trees? And so on 

 and so on ; all of which makes us painfully 



