8 MONTHLY NOTES ON GRUBS AND OTHER CANE PESTS. 



CANE GRUB INVESTIGATION, NOVEMBER, 1917. 



Co-operation. 



The heavy rains at the beginning of November have started the 

 emergence of the grey-back cane bettles. Now is the time for every- 

 one to be in the harness, for it is only by co-operation that we shall have 

 strength to snccessfully combat this terrible pest. The valuable in- 

 formation possessed by the growers, if collected and properly sum- 

 marised, might enable us to complete our investigations several years 

 earlier than if we were left to work out all the problems ourselves. 

 Each one owes it to his own interest, as well as to the interest of the 

 industry, to send in any information that he possesses along the line 

 of the questions published on -page 383 of the September Sugar Journal. 

 We are placing considerable faith in cultural methods, and desire all 

 possible evidence. However, there must be no let-up to the collection of 

 both beetles and grubs for the present, or, at least, until we discover a 

 more economical method of control. I cannot urge this collecting too 

 strongly, for there appears to be a lack of interest among growers, 

 now that a new Entomologist is appointed to handle the problem. Of 

 course, it is a well-understood fact that every female beetle destroyed 

 within two weeks after emergence destroys all her progeny; and it is 

 really an economical procedure if we can get them at this time. 



As I have indicated before, we can place little dependence upon 

 parasites for these native pests, and other control measures must be 

 worked out. Though collecting the beetles and grubs is expensive, the 

 expense is not prohibitive, and we know that by this method the pests 

 are destroyed. 



Use of Fires and Light-traps. 



Mr. Jarvis's experiments during 1916 certainly showed that our 

 common cane beetles are greatly attracted to lights, and this line of 

 experiments is worth following up, for it is a subject that lends itself 

 to extensive application. Numerous light-traps should be rigged up, 

 at the first appearance of the beetles. A trap can be made by simply 

 suspending a lantern over a tub of Avater, with a little kerosene on the 

 surface. The trap should be sufficiently elevated to have the light 

 visible from every direction. The flying beetles bump against the 

 glass and fall into the kerosene-covered water, where they are quickly 

 killed. 



Recent experiments with small fires are encouraging, and undoubt- 

 edly vast numbers of the beetles, during their flight, succumb in the 

 fii-es of the canefields. AnyAvay, we are continuing investigation of this 

 important matter, and advocate small fires, started just at dark and 

 kept up for about an hour, every evening, during the flight of the 



