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by depriving it of its leaves ; you also kill a young oak by the 

 same process. Take two plants of any sort ; prune one 

 freely and the other sparingly, or not at all ; the effect on 

 the stem of each will show clearly how essential are branches 

 and leaves to promote the growth of the stem. 



In botany, the talent and labours of inquirers have generally 

 been spent in the examination whether a plant belongs to this 

 class or that order ; neither chemistry nor physics, the most 

 powerful means of help to conquer prejudices and acquire 

 knowledge, have been allowed to sit in council on the exami- 

 nation of the most simple processes. The size of a plant is 

 proportional to the surface of the organs which are destined to 

 convey food to it : a plant gains another mouth and stomach 

 with every new fibre and every new leaf. Culture increases 

 the annual circles of the wood; but common injudicious 

 pruning tends to diminish them, and merely extends the stem 

 in length by throwing all the new formation of branches 

 to the top of the tree ; thence the tree acquires a slenderer 

 figure and a more delicate constitution, from greater height; 

 and being without cover of side branches, loses more by 

 evaporation and receives less moisture from the ground. The 

 principal process of vegetation, (assimilation by the leaves) 

 being reduced by pruning, and carried on under a diminished 

 supply of nourishment from the ground, is less productive of 

 new assimilized matter, and this smaller quantity requiring 

 to be extended along a greater length of stem, the annual 

 rings are necessarily thinner. A forest tree, perfect in all 

 its parts, has been compared to a well-regulated mixed go- 

 vernment ; the bole or stem representino^ the monarch, the 

 larger branches the nobility, the smaller branches the gentry 

 of different degrees, the leaves the people, and the roots 

 the laws on which the whole fabric rests. Pruning, let it 

 be observed, is itself a violence done to the plant, and call 

 it by what name you will, all pruning is mutilation, and to 



