CHAPTER XIV 

 GRAPE PRUNING AND TRAINING 



213. Principles of grape pruning. In addition to 'the 

 general principles that apply to all plants discussed in 

 Chapter V are several that apply especially, or even per- 

 haps exclusively, to the grape. 



a. Since the youngest growing parts, including the 

 leaves, derive all their food from other parts, they act as 

 parasites (Chapter III, 90). When mature they deliver 

 food to the balance of the plant. Hence whatever de- 



FIG. 253 GOOSEBERRY AFTER PRUNING. SAME AS FIG. 252, BUT PRUNED 



velops superfluous growth or impairs mature active leaf 

 functions, as in the case of insect or disease attack or 

 injudicious pruning, proportionately inhibits fruit pro- 

 duction possibilities, and if excessive may starve the vine. 

 b. The tendency for a vine or a vine part to be fruitful 

 is in inverse proportion to vegetative activity. Hence, 

 practices which augment such activity tend to reduce 



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