THE JOURNAL 



OF 



THE DEPARTMENT OF AGRICULTURE 



OF 



PORTO RIGO 



Vol. II January, 1918 No. i 



EXPERIMENTAL WORK ON THE CONTROL OF THE WHITE 



GRUBS OF PORTO RICO. 



By R. T. CooTTON, Entomologist, Insular Experiment Station. 



The white grubs of Porto Rico are known to have been present 

 and doing damage on the Island for the last twenty-five years. How 

 serious their ravages were previously we do not know, but since that 

 time they have become gradually more and more destructive, until 

 at present it is impossible to grow ratoon cane in some sections oT 

 the Island. 



During the year of 1908 the sugar cane in the district of Gua- 

 nica Central began to suffer very noticeably from the attack of the 

 white grubs, and the following year, matters becoming still worse, 

 strenuous measures were started for discovering methods of con- 

 trolling this serious pest. 



From that time until the present, numerous and varied experi- 

 ments have been conducted by various entomological workers of 

 the Insular Experiment Station of Rio Piedras and the Federal 

 Experiment Station, both independently, and in co-operation with 

 the management of Guanica Central and other centrals of the Island. 



No report has ever been published on the results of the vast amount 

 of experimental work conducted .along these lines, and althougli the 

 majority of the results are of a negative nature, tliey are of con- 

 siderable interest and some value to entomological workers. There- 

 fore the writer has prepared this brief review. 



A considerable portion of the work was carried out hy tlic lat.' 

 Mr. C. T. Murphy, in charge of the experimental work at Guanica, 

 .in co-operation with Mr. W. V. Tower, formerly entomologist of 

 the Federal Experiment Station at Mayagii(>z, and Mr. D. L. Van 

 Dine, former entomologist of the Experiment Station of the Sugar 

 Producers' Association of Porto Rico. Portions of the work have 

 also been conducted by INIessrs. Thos. H. Jones and G. N. Wolcott, 



