The Peach-Tree Borer. 201 



borers below tlie danger limit. AVe feel quite sure that it would 

 not lessen the numbers of borers to allow such cultivated orchards 

 to grow up to weeds or grass, but we have found no conclusive data 

 on this point. Both cultivated and uncultivated peach orchards 

 may suffer severely from the peach-tree borer, but the one who cul- 

 tivates has several advantages ; his orchard is always an advertise- 

 ment to his thrift ; it usually pays the best ; and it is much easier 

 to tight the borers in a cultivated orchard. 



Some general details regarding our experhnents. — Realizing the 

 lack of deiinite experimental information regarding the so-called 

 " remedies " for borers. Professor Comstock planned in 1892 the 

 most extensive and detailed experiments against the peach-tree 

 borer* ever attempted. In the fall of 1892 an orchard of nearly 

 400 peach trees of live different, leading varieties was set near the 

 insectary. As the sole purpose of the orchard was for experiments 

 against the borers, and as the space was limited, tlie trees were set in 

 seven long rows six feet apart and only three feet from each other 

 in the row. The location proved to be well adapted to our purpose. 

 The trees grew well and several badly infested "old relics" of 

 peach trees adjoining the experimental orchard insured a good crop 

 of borers in the orchard each year. This last condition was a very 

 important factor in the success and relative value of our experiments. 

 The trees were budded stocks from the nursery, and about one-third 

 died during the winter of 1892-1893, while about one-half of the 

 remaining buds failed to start in the spring. The dead trees were 

 replaced by more budded stock in the spring of 1894, thus the 

 experimental orchard consisted of 275 budded stocks (about half of 

 which had just been set) of five of the leading varieties, and about 

 125 trees of natural varieties grown from the pits, when our experi- 

 ments with remedial measures were begun in the summer of 1894. 

 The experiments were carried on during 1894, 1895, 1896 and 1898, 

 no applications being made in 1897. The make-up of the orchard 

 remained practically the same during these years, except that a few 



* The plans also included experiments against the apple-tree borer (Saperda 

 Candida) and the experimental orchard was started, but owing largely to lack of 

 the borers, and also to the fact that the peach-tree borer experiment took so much 

 of our time, we have not yet tested any remedial measures for the apple-tree borer. 



