GRAPE-PRUNING ON THE PACIFIC SLOPE 179 



shoots will usually be obtained from the lower buds of the 

 fruit canes. 



Choice of a system. 



In choosing a system, we must consider carefully the char- 

 acteristics of the particular variety we are growing. A variety 

 which bears only on the upper buds must be pruned "long/' 

 that is, must be given fruit canes. It should be noted that many 

 varieties, such as Petite Sirah, which will bear with short prun- 

 ing when grafted on resistant roots require fruit canes when 

 growing on their own roots. In general, grafted vines require 

 shorter pruning than ungrafted. If pruned the same, the 

 grafted vines may overbear and quickly exhaust themselves. 

 This seems to be the principal reason for the frequent failure of 

 Muscat vines grafted on resistant stock. The cultural condi- 

 tions also affect the vine in this respect. Vines made vigorous 

 by rich soil, abundant moisture, and thorough cultivation re- 

 quire longer pruning than weaker vines of the same variety. 



The normal size of the bunch is also of importance. This 

 size will vary from one-quarter of a pound to 2 or 3 pounds. It 

 is difficult to obtain a full crop from a variety whose bunches 

 are very small without the use of fruit canes. Spurs will not fur- 

 nish enough fruit buds without crowding them inconveniently. 

 On the other hand, some shipping grapes may bear larger crops 

 when pruned long, but the bunches and berries may be too small 

 for the best quality. 



The possibilities of development vary much with different 

 varieties. A Mission or Flame Tokay may be made to cover 

 a quarter of an acre and develop a trunk fcrur or five feet in cir- 

 cumference. A Zinfandel vine under the same conditions would 

 not reach a tenth of this size in the same time. Vines in a rich 

 valley soil will grow much larger than on a poor hillside. The 

 size and shape of the trunk must be modified accordingly and 

 adapted to the available room or number of vines to the acre. 



