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BULLETIlSr 446, U, S. DEPAETMENT OF AGEICULTUEE. 



Many men thin two or thxPee times dm"ing the season. The size and 

 age of the tree have considerable bearing on the length of time required 

 for this operation. 



There are two methods of thinning used in the valley, with shears 

 and by hand. The length of time required for each of these methods 

 is affected not only by the efficiency and experience of the operator 



0. Center-pole-and-wire prop. D. Single-pole prop. 



Fig. 3. — Four methods of propping apple trees in Wenatchee Valley. The single-pole prop is most com- 

 monly used. 



but by the density of the foliage and the equipment which it may be 

 necessary to use on account of the size of the tree. 



In some seasons it is of course necessary to thin more heavily than 

 in other seasons. When a large crop is expected heavy pruning is 

 done the winter before, and in that way some of the work of thinning 

 is obviated. Under normal conditions the trees of the valley usually 

 bear a heavy crop every other year. 



