60 BULLETIN 746, TJ. S. DEPARTMENT OF AGRICULTURE. 



pose that burning the trash would give us any real protection from the borer. 

 Cultural conditions in Louisiana are so different from ours that the burning 

 of the trash is practically a necessity and it is universally practiced. 1 We do 

 not, however, find that this gives them any immunity from the borer. On the 

 contrary, they suffer fully as much as we do. This very likely may be due to 

 tbe fact that burning destroys borer parasites as well as borers. There is good 

 reason to believe that here in the West Indies borer parasites of one kind or 

 another are sufficiently abundant to play an important part in holding this pest 

 in check. There is no point more urgently in need of careful investigation. 

 Until it is fully determined it will be impossible to outline a really satisfactory 

 campaign against the cane borer. * * * On certain fields it becomes advis- 

 able to burn the trash in order to be able by thorough cultivation to kill out 

 pernicious grasses that would otherwise ruin the fields. When and where and 

 how much to burn are questions that must always tax the best judgment of the 

 administrator. If judiciously done on a small scale it is often an advantage, 

 but if universal burning of the trash should be adopted on the advice of our 

 scientific friends it would surely result in the financial ruin of the majority of 

 the plantations in Cuba and of many in Porto Rico. 



It is believed that Prof. Earle will be proved correct in concluding 

 that burning or not burning trash is a matter for the mature judg- 

 ment of the plantation manager, in Louisiana as well as in other 

 countries. 



EXPERIMENT WITH THE HAWAIIAN BEETLE BORER PARASITE. 



The work of the entomologists of the Hawaiian Sugar Planters' 

 Association Experiment Station is too well known to need any ex- 

 tended description. Suffice it to say that under the auspices of the 

 very progressive sugar planters of Hawaii the world was searched 

 for parasites of insects destructive to sugar cane; that they found 

 many parasites; and that they succeeded in establishing many of 

 them in the cane fields of Hawaii. The injury from insects has 

 been greatly reduced and millions of dollars' worth of sugar is being 

 saved annually. 



The parasite which contributed largely to the control of the weevil 

 borer (Rhdbdocnemis [/Sphenopkoiios'] obscurus Boisduval) was a 

 tachinid fly {Ceromasia sphenophori Villeneuve) which was brought 

 from New Guinea. As the habits of this beetle borer in boring 

 through the cane stalks are much the same as those of the moth borer 

 in Louisiana, the junior author suggested that Ceromasia be tried 

 against the moth borer. The same suggestion was made later by 

 Dr. L. 0. Howard and Dr. W. D. Hunter, of the Bureau of Ento- 

 mology. Mr. Frederick Muir, of the Hawaiian Sugar Planters' Ex- 

 periment Station, who had discovered the parasite and introduced it 

 into Hawaii, was consulted, and gave his opinion that it would not 

 attack the moth borer. He stated that he had seen the moth borer 

 {Diatraea sp.) and the beetle borer working together, and that Cero- 

 masia confined itself to its beetle host. 



1 Prof. Earle is writing of conditions in Porto Rico and Cuba, with which he is more 

 familiar, and takes it for granted that burning the trash in Louisiana, at that time 

 universally recommended, is a necessity. 



