SUMMER PRUNING 415 



the old arms or trunk of the vine. Shoots which 

 start from the very base of the old cane are usu- 

 ally weak, and should be removed. Buds in this 

 position are shown at a a, in Fig. 261. The sec- 

 ondary or axillary branches, which often start 

 from the base of the season's shoots, should be 

 removed or broken out. These superfluous shoots 

 are pulled off from time to time as they appear, 

 or the buds may be rubbed off before the shoots 

 begin to grow. 



The heading -in of the main canes, while desir- 

 able for the purpose of keeping the vine within 

 bounds, is apt to cause a growth of laterals which 

 choke up the vine, and which do not mature, and 

 in those styles of training in which very little 

 wood is allowed to grow, the practice may pre- 

 vent the development of a sufficient amount of 

 leaf surface to properly sustain the vine. Vines 

 are often weakened by summer pruning. These 

 dangers can be overcome by careful attention, 

 however, especially by heading-in very lightly, and 

 by doing it as late in the season as possible, when 

 new lateral growth does not start readily. The 

 necessity of much heading-in has been largely 

 obviated in late years by the adoption of high and 

 drooping systems of training, and by setting the 

 vines far apart. The strong varieties, like Con- 

 cord, Brighton and Niagara, should be set ten 

 feet apart in the row, especially if grown upon 

 the Kniffin system. Catawba, being a very up- 



