BULLETIN 193. PRUNING AND TRAINING OF YOUNG VINES. 153 



The shoot should be topped within 1 or 2 inches of the top of the 

 stake, if the stakes have been chosen and driven as advised above 

 (see Fig. 4, c). This will insure the growth of laterals just where they 

 are needed for the next winter pruning. 



The vines on which a cane has been left and tied up during the pre- 

 ceding winter must be treated a little differently. The removal of 

 underground shoots or suckers is the same. Instead of thinning out 

 the shoots to a single one, as for the vines just described, all the shoots 

 should be left to grow, except those too near the ground (see. Fig. 5, b). 



As a rule, all shoots between the ground and the middle of the stakes 

 should be taken off. It is even more important that this should be 

 done early than in the case described above. If the lower shoots are 

 allowed to become large and then removed, not only is the vine weak- 

 ened by the removal of mature leaves, but the stem of the vine is 

 suddenly exposed to the direct rays of the hot sun and is very liable to 

 injury. This injury does not show by a peeling off of the bark as with 

 fruit trees, but by a general weakening and dwarfing of the vine. 



The shoots coming' from the upper half of the cane are to form the 

 spurs for the following winter pruning, and can often be left to grow 

 without further treatment. 



If the growth is very rapid and succulent, however, it is necessary to 

 pinch them, or the first heavy wind may break them off (see Fig. 5, c). 



Pinching consists of the removal of 1 or 2 inches of growth at the 

 extreme tip of the shoot. This delays the growth in length temporarily 

 and gives the shoot time to strengthen its tissues before its length gives 

 too much leverage to the wind. This pinching usually has to be 

 repeated at least once. 



Pinching may be replaced by topping a few weeks later, but the latter 

 is somewhat weakening to the vine. 



In all summer pruning that is, removal of green shoots and leaves 

 of young vines, two things should be kept in mind: First, that all 

 summer pruning is weakening; second, that the object of summer prun- 

 ing of young vines is to direct the growth as much as possible into 

 those parts which are to become permanent portions of the mature 

 vine. The weakening effect is almost nil if the shoots or tips are 

 removed when they are very small, but may be very serious if large 

 shoots are removed or heavily topped. When a large shoot covered 

 with leaves is removed it 'is a total loss to the vine. .When a small 

 shoot is removed the food materials which would have gone into that 

 shoot are diverted to the shoots that remain, and the vigor and size of 

 the latter are increased. 



