NOTES ON THE VARIOUS SPECIES 245 



to profitable bearing is now very much talked 

 about. The impression seems to prevail that no 

 tree is so bare-limbed and decayed but that it can 

 be restored to bushy, fruitful vigor. It may be 

 true that there is hardly a tree which cannot be 

 improved by pruning and fertilizing, but the po- 

 mologists of the Ohio Experiment Station, who 

 have studied this matter carefully, assert that re- 

 juvenation cannot be a commercial success when 

 practised upon trees more than thiity or forty 

 years old, upon trees in an advanced condition of 

 debility and decay, or upon trees with long, bare 

 limbs and high, thin tops. It costs more to bring 

 such trees back into bearing (if it can be done at 

 all) than it does to plant young trees and cultivate 

 them until they become profitable. 



If an attempt is made to restore vigor to apple 

 trees which contain large cavities, the success of 

 the restorative measures should be assured, as 

 has been said, before the filling is done. In most 

 cases the open system of wound treatment, in- 

 volving cleaning, draining, and dressing, but not 

 filling, is preferable to filling. 



It may be well to append here a sketch program 

 for restoration work upon old apple trees, even 

 though this one may not be much unlike programs 

 which have been suggested in other connections. 

 The first three processes should be carried out im- 

 mediately. 



