384 REPORT OF STATE BOARD OP HORTICULTURE. 



not sure how the stems acted on the insect, but our results indicate that, 

 where tobacco stems are cheaply obtainable, they will prove a good preven- 

 tive from the attacks of the peach-tree borer. 



Mounding — By this old and much-discussed method we apparently kept 

 out from one-half to seven-tenths of the borers. We do not understand just 

 how the mounds of soil keep out the borers, and we doubt if it would give 

 as good results if not practiced in connection with the "digging out " method. 

 The mounding method evidently has considerable value as a preventive and 

 is perhaps the cheapest method yet devised. It is the most practicable 

 method yet suggested for combating the insect in nurseries. 



Paper protectors — In the early days, cloth and similar protectors were 

 used, but all were soon superceded by the less expensive and equally as 

 effective paper bandages. We kept out from one-half to seven-eighths of 

 the borers with the tarred paper jirotector shown in Fig. 54. And doubt- 

 less, where rains and winds are not too prevalent to interfere with an 

 ordinary newsjaaper protector, it would give equally as good results as the 

 tarred paper; some rejoort injury to th» trees by the use of tarred paper, 

 but our trees suffered no injury from its use. Pajjer i^rotectors, when care- 

 fully put on and kept intact during the danger period, will prove a valuable 

 and very cheap preventive measure, especially when combined with the 

 ' ' digging out " ' method. 



Wire-cages — Wooden boxes or tiles placed around the trees are too expen- 

 sive, and the evidence shows that they afford little protection. The device 

 shown in Fig-. 55, however, is strongly recommended by most recent writers, 

 and, theoretically, it is an ideal protection from the ravages of this pest. 

 We confidently believed that we had solved the problem of how to keep out 

 the borer when we placed these wire mosquito-netting cages around some 

 of our trees. But it was a case of misplaced confidence, for our theory was 

 completely demolished when we examined the caged trees next year. The 

 cages apparently proved an attraction to the insect, for nearly twice as 

 many borers got into the caged trees as into those untreated. 



Washes — The favorite method of preventing the ravages of the peach-tree 

 borer has been, for at least a century, by the use of a wash of some kind. 

 More than fifty different washes have been concocted, most of which are 

 valueless as preventives, and some of which will injure or kill the trees. 

 We tested eighteen washes. 



An asafoetida and aloes wash was not offensive enough. 



Tallow should have given good results, theoretically, but it provt u 

 wholly useless ; this was a great surprise to us. 



Ordinary soap, or whale-oil soap, even two applications, ottered little av 

 no protection. The addition of paris green to a soap wash will not increa-e 

 its effectiveness, and it may injure the trees. Carbolic acid soaps, or tit- 

 Shaker wash would afford no more jjrotection than ordinary soaps, ^ve 

 think. 



Whitewash, or whitewash and linseed-oil washes were wholly ineffectual 

 in our experiments. We doubt if whitewash and glue, or bordeaux mixture 

 have better preventive qualities. 



By making two applications the same season of Hale's celebrated wash. 



