Oryctes Rhinoceros Defies The

[?] in Samoa [?] Negative

Best Efforts Of Science

Experiments to test the possible control of the rhinoceros beetle with insecticides and (b) with attractant chemicals left still unsolved problem of dealing with the No. 1 coconut pest of New Guinea, Wpet Samoa anrl Tnmra , west aamoa and longa.

Y were carried out in West imoa by entomologist Dr. R. A.

Limber, whose findings have published in a South Pacific tission circular.

Cumber, in his report on indes, said that unless relative m from attack could be proby a simple infrequent crown ation, their use could not be ed. no cases were the monthly ations made during the tests sful in keeping the crowns 3tely free from beetle attack. cticidal application would be :tical for the greater part of imoan coconut areas. The dif- ;s attached to its application were so great in comparison ombatmg the beetle through anitation and plantation con-

solidation that insecticidal control was not worth considering.

Dr. Cumber’s other tests were in tended to ascertain whether chemicals known to have an at tractive influence over certain in sects could exert a similar influ ence over the rhinoceros beetle.

He said log-trapping in West Samoa could in some areas take up to one-quarter of the beetle popula tion present and an increase in efficiency of traps by, say, 100 per cent., through use of an attractant, could have been a very important contribution.

Dr. Cumber devised three types of olfactometer to test possible attract ants but the results were negligible, In the field testing of attractants, two types of traps were set up on the margins of the Vaipoto planta

tion, where there is a high beetle population and serious damage. t ? n case a fow beetles were

7^ unlikely that “

fntnSP™ wi l? in the foreseeable cumber^eno^pd™ 1 measures >” Dr in oenernJ .

Z, 9 eT Comments 071 insectl- Cldes> Dr Cumher made ese P° mts: Their successful use in combating the beetle is likely to be extremely limited.

Insecticides can at most be only partly successful as a temporary ex pedient where sawdust or compost is concerned.

Screening and the use of in secticides where compost pits of limited size are involved may be justified but there is no justification for a long-term policy involving the spraying of such accumulations as town dumps and sawdust pits, Concreting of timber yards and approaches, adequate disposal of new sawdust, and burning or bury ing of town refuse, organic materials etc., are the only procedures in any way justified if the aim is a per manent solution.