INSECT CONTROL

Hokitika Guardian, 19 December 1930, Page 5

INSECT CONTROL

VALUE OF RESEARCH.

VIGILANCE required

NEW ZEALAND'S POSITION.

The need for greater vigilance to prevent injurious insects and diseases lrom entering New Zealand is emphasised strongly by Dr D. Miller, entomologist at the Oawthron Jnst-i----tuce, Nelson, in a report prepared lor the Department of .fecientiiic and Industrial Research, alter returning from an extensive trip abroad.

“From my observations abroad, 1 ’ Dr Miller says, “1 am more convinced than ever that the development of a practicable system to restrict in jurious insects and diseases from entering New Zealand should be seriously considered. No doubt, it is our geographic isolation that is responsible for the prevailing lethargic outlook on the subject even in the lace of past experiences, and while every year we have evidence of the ways and means by which noxious insects are able, and do actually, reach our shores.

“Though there exists at oresent a system for the protection from chance introductions of noxious insects and diseases of domestic anima.i and horticultural and agricultural crops, it is quite inadequate for the purpose for which it iw established; further, it affords no protection whatsoever to our exotic forests and plantations, which remain in their present state of comparative freedom from d e pro>l dations through chance more than anything else. MAXIMUM PROTECTION. “It is not disputed that no measures can be formulated by which all. insects and diseases would be prevented from entering a country; but every effort should be made to give the maximum measure of protection possible, and in this a practicable system of quarantine and inspection would play an important and effective part. Tile operation of ■ such a system,. requiring the senvices of a , reliable staff -and involving considerable expense, would be justified.” During the 33 weeks he was away, .Dr Miller visited Fiji, Hawaii, the United States, Great Britain,' France, Italy, Germany, Belgium, Equador, Chile and Peru. He stated in his report that much attention was g*ven bj him to methods adopted in ether countries to check the ; blackberry ■ pest. He arranged for shipment from the United States of several kinds of insects that attack all parts of the plant. Inquiries were also made in various parts of the world, with varying success, Tor parasites for ragwrot, gorse, piripiri, and other noxious weeds. Investigations were made in Scotland into an unidentified disease that attacked and killed bracken, It vas found that largo patches that were breast-high three years previously, had 'been left almost completely bare, and that pasture was taking a rapid hold. At the outset of this .strange infestation the bracken suddenly wilted, and it was dead in ten days. The following season’s growth was stunted, and in the third year the bracken was completely dead.,

MOSQUITO CONTROL. | The greater part of the forest pioblems investigated related to the control of the bark beetle, attention also being given to the control of insects infesting nursery stock. Important data were obtained on thepo questionS ) and also upon many problems connected with orchard and agricultural problems. Referring to the control of mosquitoes and sandflies, Dr [Miller states: “Apart from the mechanical and insecticidal control of mosquitoes some good results have been secured by using predaceous insects and fish. In the Hawaiian Islands there has been successfully established a non-blood-sucking species of mosquito, flie larvae of , which are predaceous upon those of other and blood-sucking forms. In North America the fish, Gambmsia affinis, was introduced into Sacramento waters from Florida; this fish was transported in large cans under cool store, conditions. It should be possible to transport the predaceous mosquito and fish to New Zealand.” Discussing the work of the Institute of Entomology, Dr Miller said it was necessary to emphasise that in order to enable the institute to maintain its efficiency and to meet the increased demands being made upon ' its services, additional grants were required from the overseas contributing Governments. New Zealand at present contributed £4OO -a, year, and it was suggested that this should be increased by £2OO. “The most conclusive evidence of the utility of the Institute of Entomology,’’ he said, “is found in the activities of the Parasite Laboatory at Farnham Royal; this'applies specially to New Zealand, and the figures show that of the parasites sent from the laboratory to various warts of- the Empire, this Dominion absorbs more than half the output.”