IS GRAFTAGE A DEVITALIZING PROCESS? 151 



increase the longevity and virility of the plant. Plants which are given 

 an abundance of food and are protected from insects and fungi and the 

 struggle with other plants, are better equipped than those left entirely 

 to nature. It is the commonest notion that cultivation is essentially an 

 artificial stimulus, that it excites the plant to performances really beyond 

 its own power, and therefore devitalizes it. But this is a fallacy. All 

 plants and animals in a state of nature possess more power than they 

 are able to express, and they are held in a state of equilibrium, as Mr. 

 Spencer puts it, by the adaption of environment. Once the pressure of 

 existing environment is removed, the plant springs into the breach and 

 takes on some new features of size, robustness, or prolificacy, or distrib- 

 utes itself in new directions. The whole series of benefits which arise 

 from a change of seed is a familiar proof of this fact. So that, if cul- 

 tivation, domestication, or in other words, unnaturalness, may be some- 

 times a stimulus, it is not necessarily so. Cultivation differs from natural 

 conditions more in degree than in kind. Or, as Darwin writes, " Man 

 may be said to have been trying an experiment on a gigantic scale; and 

 it is an experiment which nature during the long lapse of time has neces- 

 sarily tried." 



3. It is said that own-rooted plants are better than foster-rooted. This 

 is merely an assumption, and yet it has been held with dogmatic positive- 

 ness by many writers. If mere unnaturalness, that is, rarity or lack of 

 occurrence in nature, is no proof of perniciousness, as I have tried to 

 show, then this statement admits of argument just as much as any other 

 proposition. And surely at this day we should test such statements by 

 direct evidence rather than by a priori convictions. And here I will 

 repeat that the citation of any number of instances of the ill effects of 

 graftage is no proof that own-rooted plants are necessarily better, if there 

 should still remain cases in which no injurious effects follow. Now, if 

 it is true that " own-rooted things are in all ways infinitely better, 

 healthier and longer lived " than foster-rooted plants, and if " grafted 

 plants of all kinds are open to all sorts of accidents and disaster," then 

 the proposition must admit of most abundant proof. I will analyze the 

 subject by discussing the following questions: a. Is the union always 

 imperfect? 6. Are grafted plants less virile than own-rooted ones? 

 Are they shorter lived? 



a. It is well known that the physical union between scion and stalk 

 is often imperfect and remains a point of weakness throughout the life 

 of a plant. But this is not always true. 



There are scores of plants which make perfect physical unions with 

 other plants of their own species, or even with other species, and it fol- 

 lows that these, alone, are the plants that should be grafted. The very 

 best proof which can be adduced that the union may be physically per- 

 fect, is to be found in the micro-photograph of an apple graft published 

 two years ago in the American Garden by my former associate, Profes- 

 sor C. S. Ck and all.* The cells are knit together so completely that it is 

 impossible to determine the exact line of union. I have in my posses- 

 sion a number of the micro-photographs, taken by Mr. Ckandall, which 

 show the same condition.f Mr. Ceandall also figures, on the same page, 

 a microscopic section of an apple graft in which the union is very 

 poor, but this graft was made in a different manner from the other; 

 and that is another proof that the operation should be suited to the 

 subject. 



* American Garden, XI, 65. 



t These were exhibited at the Convention. 



