No. 4.] TREE SURGERY. 469 



uiitbrtuiiatelj so limited by\ tlie discontinuance of the work 

 in 1900 that some questions raised in the mean time cannot 

 be fully answered. The loss of some of the most valuable 

 records of the work of later j^ears has also been a great dis- 

 advantage. 



The results of })runing trees of different species should 

 be studied for at least ten years more. Cutting, by the 

 owners, of many of the trees under observation, since the 

 cessation of the gypsy moth work, was unfortunate, as it 

 rendered the completion of our observations on these trees 

 impossible. If such experiments could be carried on by a 

 board having entire and permanent control of the trees 

 operated upon, the records obtained would be far more 

 satisfactory. The results of scraping the bark of trees 

 should be further investigated by some one capable of doing 

 the work with scientific accuracy. If carefully conducted 

 experiments on all our shade and fruit trees could be carried 

 out for fifteen or t^venty years by the Agricultural College, 

 the results would be far more valuable than those of the 

 necessarily intermittent and incomplete work, some results 

 of which have been briefly given here. 



