168 MANUAL OF AMERICAN GRAPE-GROWING 



When the five shoots grow, the height of the head will be 

 determined at the next winter pruning by which of the corre- 

 sponding canes are left as spurs. If the highest two canes 

 are cut back to spurs and all others removed, the vine will 

 be headed as high as possible, as these two spurs form 

 the two first arms which determine the length of the trunk. 

 If the lowest two canes are chosen aiijd all of the vine above 

 them removed, the trunk will be made as low as possible. 

 Intermediate heights can be obtained by using some other 

 two adjacent canes and removing the rest. It is often advis- 

 able to leave some extra spurs lower than it is desired to head 

 the vine and to remove these lower spurs the following winter 

 after they have borne a crop. For example, the three or four 

 upper canes might be left, if the vine is vigorous enough, and 

 the lowest one or two of these removed at the next pruning. 

 This, however, is not often necessary with properly handled 

 vines and is objectionable because it makes large wounds in 

 the trunk. 



Third winter pruning. 



At the end of the third season's growi:h the vine should have 

 a straight, well-developed trunk with a number of vigorous 

 canes near the top from which to form the arms. 



Figure 28 represents a well-grown vine at this period. Xo 

 shoots have been allowed to grow on the lower part of the 

 trunk and the five buds allowed to grow above have produced 

 nine vigorous canes. The primer should leave enough spurs 

 to supply all the fruit buds that the vine can utilize. The 

 number, size and thickness of the canes show that the vine is 

 very vigorous and can support a large crop. It will depend 

 somewhat on the variety how many buds should be left. For 

 a variety whose bunches average one pound, and which pro- 

 duces two bunches to the shoot, twelve fruit buds should give 

 about twenty-four pounds, or about seven tons per acre^, if the 



