^otes on Insects T)amaging Sugar-Cane 

 in Queensland 



^^-(^^ 



By EDMUND JARVIS, Entomologist 



INTRODUCTION. 



During the course of recent experimentation relative to the control of 

 *' white grubs " in our Northern canefields opportunities were afforded 

 for studying the economy of common insect pests of this important 

 plant, some of which, although fortunately less harmful than certain 

 species of root-eating Scarabaeidae, are nevertheless decidedly injurious 

 to sugar-cane, and have not hitherto been figured or described. This 

 research work was conducted under the direction of the Bureau of 

 Sugar Experiment Stations, at Gordonvale Experimental Laboratory, 

 situated in the Cairns district — a sub-tropical portion of the State 

 favoured with an annual average rainfall exceeding 92 inches, while 

 the yearly minimum and maximum temperatures range respectively 

 from 684 to 83-7 degrees Pahr. The land around Gordonvale is for 

 the most part of volcanic origin, formed of friable soils varying in 

 colour from light-red to chocolate, the latter class being as a rule deep 

 and exceedingly fertile ; but includes also extensive alluvial deposits 

 composed of rich sandy or clay-loams eminently suitable for the culti- 

 vation of sugar-cane. 



The surrounding country, which is uniformly flat and almost en- 

 circled by mountain ranges, supports a somewhat stunted vegetation 

 consisting principally of eucalypts and acacias, with an undergrowth 

 of coarse grasses interspersed with various low-growing herbaceous 

 plants. 



The following notes must be considered simply as a brief record 

 of field and other observations, made during a period of about twelve 

 months, and confined almost exclusively to a very limited area within 

 two miles radius of Gordonvale. 



Messrs. Girault and Dodd have recently published details of pre- 

 liminary work regarding the metamorphosis of several injurious cock- 

 chafers (Qld. Bureau Sugar Expt. Stns., Div. Ent., Bull. No. 2, 1915), so 

 that in dealing with this section of cane pests (Section E in the present 

 bulletin) I have avoided a recapitulation of facts already known, and 

 merely recorded personal observations on the control, parasitism, and 

 general appearance of adults of our more important root-eating cane 

 beetles, referring the reader to Bull. No. 2 of this Bureau for data 

 respecting the life-cycle of Lcpidiota albohirta and other allied forms. 



