Improved varieties of JVeio York Fruit Trees. 91 



fine new varieties, of pears, for instance, will not attain a duration 

 of more than fifty or sixty years! 



That the theory here briefly stated is, in some degree, correct, 

 no one who is acquainted with the details of vegetable physiol- 

 ogy, as understood at the present day, can reasonably doubt. 

 The question, however, is, what may be the probable duration 

 of a healthy variety, and what are tlie causes which hasten its 

 deterioration and decay? 



From many and repeated observations, we have been drawn 

 to the conclusion, that the duration of any given variety of fruit, 

 which has been originated from a healthy parent, may be prop- 

 agated for two or three, if not for many, centuries. We do not 

 believe that the grafts taken from the original tree of a certain 

 variety inevitably follow the same laws of nature, and are affec- 

 ted by the same period of decay, as that original tree; but we 

 are rather inclined to the belief, that the sudden decay of any 

 given variety arises from causes depending upon the manner of 

 its propagation, by grafting or otherwise, when a proper attention 

 is not paid either to the healthiness of the stocks grafted upon, 

 or to the grafts themselves. We conceive this opinion receives 

 additional support from the fact, becoming every day more clear- 

 ly understood by physiologists, that the buds are as entirely and 

 decidedly distinct individual plants as the seeds themselves; al- 

 though they may undoubtedly, when separated from the parent 

 stem, more readily carry with them and perpetuate any feeble- 

 ness or disease inherent in the variety, than the seeds of the 

 same. 



It may be inquired by those who have unhesitatingly adopted 

 Mr. Knight's theory, how then do we account for the extinction 

 of some of the finest old varieties of fruit in those very districts 

 and countries where they originated? Why are the Golden pip- 

 pins, the Nonpareils, &.c. no longer thrifty and productive in 

 England, as formerly? Why do " we no longer see the beurre's, 

 the St. INIichael, the St. Germain, and other pears, as before, in 

 the markets of Paris?" The usual answer is that these varieties 

 are extinct, from sheer old age, that their period has passed by, 

 and they should be cast away as no longer worthy of cultivation. 

 With all due deference, we cannot believe a word of this. On 

 the contrary, we have not the slightest doubt that the fine kinds 

 of fruit have only become " miserable outcasts " from having 

 been carelessly and improperly propagated. 



Accumulated experience has taught us that the stock and the 

 graft exert a reciprocal influence upon each other. That as an 

 unhealthy stock may communicate its disease to the graft growing 

 upon it, so, also, a healthy stock may be affected by inserting in 

 the same a diseased graft. Many variegated leaved plants (which, 

 though generally admired, are but diseased varieties,) are prop- 



