310 PRINCIPLES AND PRACTICE OF PRUNING 



for grapevines, certainly of American varieties, is the 

 trellis. Though there are several forms, depending upon 

 the system of training, they all agree in the main points 

 of construction. Posts of cedar, locust, chestnut or other 

 wood durable when set in the ground are spaced at dis- 

 tances depending upon the system, the character of vine 

 growth, etc. End posts must be very firmly braced to 

 withstand the weight of vines and fruit, especially dur- 

 ing the strain caused by heavy winds. Figure 266 shows 

 two ways of bracing, the most popular at A and B. 

 Number 10 or 12 wire is generally used. Because of ex- 

 pansion and contraction due to temperature the wires 

 should pass through the staples loosely and at each end 

 the slack be wound on a reel of some kind. Unless this 

 is done and the wires partly unwound in the fall, the end 

 posts and perhaps some others may be pulled loose dur- 

 ing winter. 



222. Other supports than trellises and stakes. Tn ama- 

 teur practice grapes of all classes are largely grown upon 

 arbors, porches, fences, buildings, trees, etc. The first 

 is often excellent as a landscape gardening feature when 

 it covers a walk. Where the principles of pruning and 

 training are adapted to the kind of support, grapes of 

 good enough quality for anyone may be so produced. 

 But for business purposes trellises and stakes are de- 

 servedly most popular because better results can be so 

 produced. The advantages of the trellis over the arbor 

 are : The trellis is cheaper and more easily built ; it will 

 last longer and can be more easily repaired ; it will double 

 the fruit-bearing surface of the vines, the size of arbor 

 and trellis being the same ; the vines will be more pro- 

 ductive and they may be pruned, sprayed and cultivated 

 and the fruit more easily harvested. 



223. The American grape (mainly Labrusca varieties 

 and hybrids) must be pruned both to prevent over- 

 bearing and to secure high quality fruit without jeopard- 

 izing the vigor of the vines. If common sense docs not 



