312 PRINCIPLES AND PRACTICE OF PRUNING 



to produce the average yield of 15 pounds — about 50 

 good-sized clusters — 20 or 30 buds, or an equivalent of 

 spurs, must be left at pruning time in winter or early 

 spring, this calculation being based on an average of two 

 clusters to each bud left. Sometimes these buds may be 

 on only one cane, but generally better results are secured 

 when two or three canes are chosen upon the main stem 

 or stems, according to the system of training employed. 

 Hence proper pruning of the grape aims to remove all 

 canes and spurs except those needed to supply the de- 

 sired number of buds and bunches. 



Pruning may be done at any time between the fall of 

 the leaves and a time two or more weeks before the buds 

 are expected to swell in spring. It is not considered good 

 practice to prune very near the time of bud swelling be- 

 cause the vines are very prone to "bleed" (15). Where the 

 winters are severe and the vines must be covered it is 

 a good practice to give a rough pruning in the fall so they 

 may be covered easily. More wood should be left in such 

 cases than is actually needed because there may be more 

 or less loss due to covering and uncovering as well as to 

 possible frost injury. The superfluous wood and buds 

 may be removed when the vines are uncovered shortly 

 before growth starts. While there is some basis for the 

 advice not to prune when the wood is frozen, it is less 

 because of any physiological reason than because the 

 wood is then very brittle and hence subject to unusual 

 breakage. 



That the system of training is far less important than 

 judicious pruning is proved by the fact that excellent re- 

 sults are secured with a considerable number of systems. 

 Nevertheless there is, between pruning and training, an 

 iiitcr-relationship that fits a certain system better than 

 any other to a given variety or environment. Hence the 

 many systems and modifications of systems seen in the 

 various grape-growing sections. Pruning and training 

 depend largely upon the fashion of the locality and the 



