72. ON THE PRUNING OF VINES. 



time to time ; and that for various reasons, the opera- 

 tion may be supposed by those who are unacquainted 

 v/ith the nature of the plant, to be intricate, and to 

 require a considerable portion of skill, yet the con- 

 trary is the fact; for, if the principle on which it is 

 to be performed be carefully kept in view, the whole 

 art of pruning a vine lies in a nut-shell. 



In order to render this art as clear as possible, the 

 reasons on which it is founded require to be distinctly 

 shown. For this purpose it is necessary to make an 

 important preliminary remark, namely; that the old 

 wood of a vine, or that which has previously borne 

 fruit, is not only of no further use at any subsequent 

 period, but is a postive injury to the fertility of the 

 plant. Tlie truth of this remark depends on the fact, 

 that every branch of a vine that produces no foliage, 

 appropriates for its own support a portion of the 

 juices of the plant that is generated by those branches 

 that do produce foliage. To prove this fact, and to 

 make it as clear as possible, it will be necessary to de- 

 scribe, briefly, and in part, the process by which the 

 life of a vine is sustained, and its parts annually 

 nourished. 



The iirst movement of the sap in the spring takes 

 place in the branches, and lastly in the roots. The 

 buds, in consequence of tlie increasing temperature of 

 the air, first swell and attract the sap in their vicinity. 

 This fluid having lain dormant, or nearly so, through- 

 out the preceding winter, becomes gradually expanded 

 by the influence of the solar rays, and supplies the 

 buds with nourishment from the parts immediately 

 below them. The vessels which yield this supply, 

 becoming in consequence exhausted, are quickly 

 filled by fluid from the parls below tJicni^ and in this 

 manner the motion continues until it reaches the 

 roots, the grand reservoir of the sap; by which time 

 the solar heat having penetrated the soil, the roots 

 begin to feel its enlivening influence. The whole 

 body of sap then begins to move upwards, and as 

 soon as the quantity propelled is more than sufficient 



