DAMAGE TO SUGAR CANE BY THE SUGAE-CANE BOEEE. 5 



in plant cane. The least injury to a cane by a borer served to throw 

 it into the infested column. The general results are shown in Table I: 



Table I. — Infestation by the sugar-cane borer. 



In addition to the canes referred to in the table, two other large 

 lots were removed from the plats for other purposes and examined 

 for borer infestation. One hundred canes were taken from a plant- 

 cane plat for determining the comparative weights of infested and 

 uninfested canes. These canes were infested to the extent of 72 per 

 cent. From a stubble plat 734 canes were removed for determining 

 the effect of the borer upon the sugar content of the cane. Of these 

 canes 393, or 53.54 per cent, were infested. Both of these experiments 

 are described in detail elsewhere. Adding these counts to the pre- 

 vious number we have a total of 3,834 canes, of which 1,313 were 

 borer free and 2,521, or 65.75 per cent, were infested by the borer. 



INFESTATION OF TOPS. 



In five instances the same number of tops as of canes were exam- 

 ined and showed a distinct correlation between the uifestation of the 

 two parts of the stalk, the infestation in the tops increasing to corre- 

 spond with the increase in the infestation of the canes. This is very 

 suggestive as to the value of clean burning of the trash after removing 

 cane from a severely infested field. The data on this point are given 

 in Table II: 



Table II. — Infestation of tops by the sugar-cane borer. 



Varieties. 



Per cent 

 infestation 

 in canes. 



Per cent 



infestation 



in tops. 



Purple. 

 D. 95... 

 D. 74... 

 Striped 

 Purple. 



CENTER OF HEAVIEST INFESTATION. 



That it is the tendency of the borers to seek the middle of the plat 

 is suggested by the fact that in 4 cases the highest percentage of 

 infestation was found in that portion, while in only 1 case was the 



