ON THE THEORY OF PRUNING FURIT TREES. 



• BY LAWRENCE YOUNG. LOUISVILLE, KY. 



A. J. Downing, Esq. — I have heretofore suggested to you my design of offering through 

 the medium of your columns, to the pomological world, the outline of a rude theory which 

 I have entertained for some years, respecting the existence of two forces or principles in 

 vegetable phj'siology, and their bearing upon the science of culture, training, and pruning. 

 It has seemed to me that the vague, indistinct, not to say contradictory notions of these 

 forces, to be learned in the books, is a frequent source of injury to the cause of fruit cul- 

 ture at large. 



In order to explain the nature of the two forces referred to, and in order to give an ex- 

 ample of the manner in which erroneous views of their nature may operate, I shall quote 

 a few authorities setting forth the axiomatic and doctrinal nature of said forces, according 

 to the present state of the science of vegetable physiology. 



Four of the best American authors. Downing, Tuomas, Barky and Kenrick, and at 

 least one English writer, Loudon, agree substantially in setting down to the account of 

 over luxuriance, the cause of unfruitfulness in trees of the orchard or fruit garden — as 

 also in stating that fruitfulness lies in an opposite direction, or at some point towards fee- 

 bleness not more remote than debility itself. Downing asserts that fruitfulness or luxu- 

 riance, or rather the causes which lead to their development, are susceptible of being ex- 

 cited, either the one or the other, at the will of the operator, by " difference in the mode 

 of pruning." The others make luxuriant wood growth and fiuitfulness two antagonistic 

 extremes, stating in substance that " whatever tends to promote one retards the other." 

 These, and such other of the best authors as I am familiar with, all admit an existence of 

 two tendencies in the condition of a tree, one to fruit-bearing, and one to the making of 

 wood-branches; all agree that fruitfulness lies in an opposite condition from wood forma- 

 tion, but in terms so general that the inexperienced are left to infer that the farther you 

 recede from luxuriance, the nearer one approaches the point of fruitfulness. In fine, high 

 feeeding, in one form or other, is set down as the great agent for exciting the system of 

 wood-buds and starvation, for bringing into activity the fruit bud. Luxuriance and un- 

 fruitfulness are used as synonymous terms, and by inference, starvation and fruitfulness 

 seem also to have the same import. My theory of these forces supposes them also to exist 

 in a state of antagonism — that the seat of the wood system is in the trunk, branches and 

 roots, between which there is evidence of a strong sympathj'', and of a continued action 

 and reaction — that the fruit-bearing system has no sympath}^ with the roots, but feeds 

 upon the juices of cii'culation in the branches, as parasitical plants — that fruit spurs once 

 developed never change their nature, except in consequence of some act of violence, and 

 may multiply like parasitical plants, until their demand upon the juices of circulation even 

 starve out the Avood-buds, and finally induce the death of the tree. Fruitfulness I consi- 

 der a state of normal health in a tree large enough to bear. I think it exhibits the exis- 

 tence of these two forces in a state of equilibrium, and a departure therefrom, towards 

 either extreme — towards luxuriance or feebleness, is a disturbance of the balance of power 

 — the beginning of a state of disease, the nature of which will entirely depend upon the 

 character of the force in predominance, and must call for remedies in accordance; that is, 

 a tree too luxuriant for fruitfulness will need depletions, while a starving subject would 

 want stimulants and tonics. 



