FRUIT PESTS AND THEIR NATURAL ENEMIES.

Hawera & Normanby Star, Volume LIII, Issue 9302, 19 March 1907, Page 2

FRUIT PESTS AND THEIR NATURAL ENEMIES.

In the history of the world's work the patient labor of the entomologist ana the marvellous results of his research ■are worthy of an important chapiter. It is only now and then, amid a multitude of records of industrial and scientific triumphs, that one beairs of a new discovery by these patient investigators, and it is seldom that due recognition is given to the years of -travel and hard work which led up to their success.

1?or some years past Mr George Com- j pere has been investigating the pests ' wluch. threaten to destroy the fruit industry of Australia. His Tesearch.es 'have i been made on behalf of the Western Aus- ' tralian Government, and' have taken him practically all ovecr tuie world. Mr Com- I pexe arrived in Sydney by the Ventura recently from one of these quests. Leaving Western -Australia, last June in search of a parasite to destroy the dreaded' fruit fly, he has tmavelled- hundreds of miles' up the rivers of Southern China, and tracked the parasite — a wasp so tiny as to be almost invisible to the naked eye— to its haunts in Central India. The entomologist does not travel by one of Cook's ioutes, and Mr Gompeire's joumeyings have often taken him into localities where the natives had (never before seen a white face or heard the sound oS. a European voice. As a Tule they have left him to "his investigfiitions with stolid indifference, thereby placing themselves on the same intellectual plane as those people who bring all such enthusiasts under the classification of "bug-hunters. If Mr Compere has achieved what he claims to have done, he has, in tne couonse of his Teoent travels, gone a long way towards settling the problem of the fruit fly and red scale pests. He says that he found in the orchards of Southern. China four species of pajKusaltes of the ired scale. He sent them on. to California, where one species was already known, and when he visited that country on his way back to A'UstraJia he found that they had increased and multiplied, and' appeared to be likely to stand the voyage to Westeam Australia. How the little immigrants have fared since then he has not yet; leaffned, but he is determined! that if they have perished the only ifching to do is to. , secure some more and persevere witih. ■their importation until they take 'hold inAustralia. He has no fears that they will not stand the climate. "Wherever, a fruit will gsrow its parasites will flourish," he said. "Not long ago theyi were saying in Victoria that the fruit fly could not live thpre. But I hear that they have it now." In the course of his wanderings in China Mpr Compere frequently did not see another BuTopeani for a week at a time. He uad to make journeys up the river in native sampans, and do all his other travelling on foot. What con-

vinced him of the efficacy of the parasite wasps, was the fact that, although, tine native fruitgrowers were notorioansly ignorant, careless, and (unscientific, their coops never suffered' to any extent, the season being, of course, that although, tine fruit diseases were always present, nature hod placed the bane and the antidote side , by .side. Take the citrus family, for instance," Mar Compere explained. "The citrus family is indigenous to Asia. The scale insects that live on them axe also indigenous and it is simply their presence that causes the pest to be held in com- j plete subjection. The Chinese are not -the people to import insectis to kill these pests; yet they do not suffer, except from the cuoumbex fly, which has been brought into the country from India." On leaving China Mr Compeire wenib ] round to India by way of Colombo, and conducted most of his- investigations at j Poona, about six miles by rail from Bom- ; bay. Here he noticed the same indifference to pests and the same freedom from eerajous consequences as in China. "I seemed a number of specimens of parasites on the fruit fly," he sand, "which I 6ent- ] to Western Australia last November. I. have .not yet learned how they fared: The difficulty lies in the .fact that these creatures ere shortlived, and develop very 1 rapidly, while the voyage is a long one. They probably deposit their eggs and gefc no results. If you place them in a cooib

chamber and allow them practically tohibernate, there is a chance of some of them surviving the trip." In connection with this phase of the matter, Mr Com-

pere expressed his iegi€t at the attitude of the Department of Agriculture of this State, which gives him no assistance ox

recognition whatever. The transhipment of these insects art. Sydney for Western Australia greatly .increases the risk of' .their perishing, yet tJie only assistance jMt Compere has receivedi has not been in Aiisfcialia, where it might be expected/but .in California, whene his specimens were taken charge of and nursedi umtiß his return.

Whether they perish or not he is determined to go on. "This is one of tihe most important mattere affecting Australia/ >he remarked. "It is a case of parasites or nothing when the question of a remedy is considered. There is mo other way of dealing •effectually with the fruit fly. In India there are et least 20 different species of fruit fly. Yet vexy little damage is done. The fruits which, are grown there, and which flies are liable .to damage, are the mango, the orange, and the guava. Contrast the immunity from damage which they experience in India, to the condition of the South African orchards. When once the black scale entered the orchards they had to spray and fumigate continually to keep the pest down. On the other hand a parasite was found iin Spain which destroys the codlin moth. It is used' in the orchards of California and New Zealand, and is doing .good wiork The San Jose scale is kept in complete subjection in California by a. parasite wasp. In Japan, where I have been

recently, they recognise this fact, and are almost immune from pests of any kind. I know that in Tasmania the orcharddsts

catch a large number of the codJin moths by tying bags round the trees, but tihey

"will have to go on doing it for evermore. Once they let up on it, the pest. is all over their fruit again." These wasp parasites are, as already

6tated, almost microscopic in size. In the case of the red scale the wasp deposits her eggs Tinder the scale, and the maggot destroys the scale as soon as ifc is hatched. The fruit fly wasp attacks its enemy while it is in the maggot stage in the fruit. These insects axe

stated to be quite harmless to man, and

not being vegetable feeders, cannot become a, pest Tipan asny fotiit. Mt Compere also found a small worm, resembling an eel worm, 'which, preys upon the fruit fly, but not being certain w to whether at was in-

6pecdments in Honolulu in order that ?>r Cobb, a well-lgiown. scientist there, night observe their habits before they were passed as desirable immigrant.

Jtiir Compere leaves fox Western AimstraJia, and on arrival he will present a report to has Government on the .resulte of his observations. — Sydney Morning Herald.