20 



BULLETIN 518^ U. S. DEPARTMENT OF AGRICULTURE. 



"squatty" appearance. Generally they are set at such a distance 

 and so pruned that there is sufficient light and air. The amount of 

 propping required depends upon the habit of growth and shape of the 

 tree, but thinning and harvesting are facilitated by heading the 

 trees low. 



The summer pruning consists usually in tipping the branches. Ac- 

 cording to the growers, the purpose is to induce more regular bear- 

 ing and to give the trees a more stocky groAvth ; however, there was 

 not enough evidence to form any definite conclusions in regard to this. 

 Many growers prune heavily one year and lightly the next. The 

 average number of trees a man will prune a day in Hood River 

 Valley, where winter pruning is practiced, is 30. The age of the 

 trees apparently did not to any extent affect the time required, as 

 Table VI will show. 



Tabtli' y^. — Influence of age on time and cost of pruning on farms studied. 



Age. 



8 to 9 years 



10 to 11 years 



12 to 13 years 



14 to 15 years 



17 years and over 



All records . 



Trees 

 pruned in 

 10 liours. 



30 



Hours of 

 man la- 

 bor per 

 acre. 



20.54 

 25.14 

 24.45 

 24.80 

 22.38 



24.36 



Cost of pruning. 



Per acre. Per tree. Per box, 



$4.62 

 5.66 

 5.50 

 6.58 

 5.04 



5.48 



SO. 07 



.OS 



$0.0223 

 .0275 

 .0252 

 .0170 

 .0236 



.0247 



The size of the orhard, like age, has little effect on the time required 

 for pruning. With the orchards arranged in five groups, according 

 to size, is is found in each group to cost practically $0.08 per tree, 

 or $0,025 per box. 



Pruning time is influenced by the variety, style, and method of 

 pruning, the system, whether alternate or annual, the amount of 

 propping and thinning the grower may practice, the thrift of the tree, 

 and peculiarities of individual trees. Taking all the orchards to- 

 gether, there was a man-hour charge for pruning of 24.36 hours, or 

 $.5.48 per acre. With 72 trees per acre, there is an annual charge 

 of $0.08 per tree, or $0.0247 per box. The cost per box for pruning 

 was practically the same for clean-cultural orchards and those under 

 a mulch-crop sj^stem of management, it costing $5.28 per acre, or 

 $0,024 per box, for the former and $5.74 per acre, or $0,025 per box, 

 for the latter. 



DISPOSAL OF BRUSH. 



Three well-defined methods of disposing of the brush are practiced 

 in this region. One way is to go through the orchard with a one- 

 horse wagon or slip boat, pick up the brush, and haul it to some 



