344 PRINCIPLES AND PRACTICE OF PRUNING 



fruit buds should give about 24 pounds, or about seven tons to the 

 acre, if the vines are planted 12 by 6 feet. The number of spurs 

 will depend on the length. Six of two buds each will give the re- 

 quired number, but where the canes are exceptionally vigorous they 

 should be left a little longer, in which case a smaller number of 

 spurs will suffice. 



When the number and length of the spurs are decided on, the 

 canes should be chosen which will leave these spurs in tlie most 

 suitable position for forming arms. This position will depend on 

 whether we want a vase-form or a fan-shaped vine. In the first 

 case, we choose those which will distribute the spurs most evenly 

 and symmetrically on all sides, avoiding any which cross or point 

 downwards; in the second, only those canes which run in the di- 

 rection of the trellis, avoiding canes which stick out between the 

 rows. Downward pointing canes may be used in this case. 



It is comparatively easy properly to shape vines which make only 

 a moderate growth during the first three seasons. On the other 

 hand, very vigorous vines may finally l)e brought into pr.ictically 

 perfect shape. The somewhat larger and more numerous wounds 

 necessary are more easily healed by a vigorous vine. 



256. Pruning after the third winter.— For the pruner who under- 

 stands the pruning of young vines and has brought them to apprnxi- 

 mately the desired form, the subsef|uent winter pruning is very 

 simple. It involves, however, one new idea — the distinction between 

 fruit and sterile wood. 



Up to the third winter pruning, this distinction is not necessary; 

 first, because practically all the wood is fruit wood, and second, 

 because the necessity of forming the \'ine controls the choice of 

 wood. From this time on, however, this distinctii>n must be care- 

 fully maile. At each winter pruning spurs of fruit wood must be 

 left to ijroduce the crop to be expected from the size and vigor of 

 the vine. Besides these fruit spurs, it may be necessary to leave 

 spurs of sterile wood to permit of increasing the number of fruit 

 spurs the following year. 



Each winter after the third the same process must be followed. 

 I'lrst, enough fruit spurs, as well placed as possible, must be left 

 to produce the crop. Second, on most vines, supplementary spurs 

 of sterile wood must be left to supply more arms where they are 

 needed, and finally, when the full complement of arms has de- 

 veloped, to supply new arms to replace those wdiich have become 

 too long or are otherwise defective. 



Sometimes it is difficult to find water sprouts in suitable positions 

 fur replacing spurs. This may be due to_ weakness of the \ines, 

 which are able to develop shoots on only the fruit spurs and have 

 no surplus vigor to force out dormant buds on the older wood. 

 This difficulty may be met by shorter pruning. If an arm is too 

 long, and at the same time weak, it should be pruned to extra short 

 spurs. This will tend to force water sprouts to start from the older 

 wood near the base of the arm. Their absence at the winter prun- 



