RANDOM NOTES

Dominion, Volume 28, Issue 284, 28 August 1935, Page 8

RANDOM NOTES

Sidelights on Current

Events

(By Kickshaws.)

A strange name appeared In the news about the Italians yesterday— King Victor Emmanuel, their King. * » #

According to a professor, the world is not a fit place for children. Well, we are beginning to wonder if it is a fit place for their parents.

American tree lovers are said to be on the look out for a tree to symbolise their country. We understand that the palm gets all the tribute. « »

“It seems to me you are called upon to decide a far greater number and far more heated quarrels than come before even the Supreme Court,” says “R.M.E.” “The argument this time is: Who was the announcer of the relay of the wrestling match on Monday, August 19, between Jagat Singh and Earl McCready, from 2YA? 1 will be very grateful for the information.” [The announcer was Mr. A. Pope.]

It is timely to see that there is to be an Empire conference to devise methods to fight the insect world We are sb concentrated on our own affairs that few of us realise that mankind’s real enemies, apart from himself, are to be fouud in the insect world. One day we will all take insects seriously. At present we only worry when they start to worry us. There are all told over 30,000 types of insect, and over 3000 wage relentless war against " mankind. They launch their attacks in so many different ways that it is impossible to tight one battle and have done with the Insects. While some flies are eating holes in the hides of cattle and doing damage to the tune of over £1,000,000 a year in England alone, another insect is eating up roofing timbers and doing many hundreds of thousands of pounds of damage every year. There seems to be an insect whose especial job it is to eat something or other. Weevils eat our wheat, codlin moths concentrate on our ap.ples. The Argentine ant. the boll weevil and tsetse fly all have their jobs. There is nothing that man uses except metal that is not attacked by some insect or other.

Now ..that the population of the world is mounting we are confronted with the fact that the onslaughts of insect pests are becoming more and more important. As soon as one pest is subdued another comes along. Some few years ago, for example, the bean beetle arrived in America from Japan in a parcel of azaleas. The bean beetle liked America. It ruined 10,000 square miles of fertile country, and is now costing £500,000 a year to fight. The trouble is that once a pest gains admittance to a country it can never be eradicated completely. We shall always have our white butterflies. Our hope is that we shall not have so many. The moment the attack against the white butterfly is relaxed they will increase. So the war goes on. Insects never know defeat. The fly, for example, still flourishes. Indeed, the fly costs England £50.000,000 a year, mainly through infantile ailments. Just how many hundreds of millions the blowfly has cost Australia and New Zealand has never been computed. In the same manner nobody knows how much damage the leather jacket would do in New Zealand if there were ne starlings.

The chief reason why man Is at present fighting a losing battle against insects is on account of their amazing fecundity. We may kill off a few thousand greenfly in the course of an hour’s work, but those left will produce 25 young each in the course of the next 24 hours. In a few days each of these youngsters, nearly all' are females, is capable of producing . tlte same number of offspring. In a week the damage we have done to the greenfly is more than replaced. If a greenfly were left unmolested for its brief span of life, that lasts about three weeks, it would leave behind a respectable family of 6000 million individuals. But for ladybirds and hover flies our gardens would be a mass of greenfly, despite our efforts. In a single, year one tiny greenfly, if left to itself, would produce greenfly whose total weight would be five times that of the whole human population of the world. We can never eradicate greenfly. All that can be done is to keep them in check. Any relaxation of the battle against greenfly means more greenfly. It Is the same with all the other insects.

While one body of people are busy fighting greenfly, another section of the community is busy fighting grasshoppers and locusts. These pests operate in a spectacular manner, and for that reason more interest Is taken in them. For four thousand years man has waged war against these two pests. For four thousand years the pests have held their own, if not increased. Despite all our modern knowledge, and despite our waging war against them with flames, explosives and poison gas, the locusts ml grasshoppers of the world continue to flourish. Female grasshoppers wil. lay anything from 600 to 800 eggs at a time. In the course of one year one grassshopper may be responsible for half a million descendants. This gives an idea of 'the magnitude of the light man is waging against these pests. If man Is to hold his own in the battle against insects he will have to use all his cunning and all his knowledge. Fumigation is not a cure. One shipment may introduce anything up to a couple of million caterpillars into a warehouse. Fumigation twill probably kill all of them except perhaps a dozen. In a few months that dozen will have turned into adults and reproduced the original total.

Scientists are well aware of the danger that threatens mankind from the insect world. The average individual does not worry much except when his cabbages are bitten threadbare or his roses grow sickly. One way of keeping the insect world subdued is to make insect tight insect. This method never eradicates, because there will always be some left. Meanwhile experiments have been made to discover just what an insect will stand. Regulation of temperature between certain limits produces sterile males in many insects and prevents propagation. If warehouses make use of this fact it is possible to prevent vast hordes of descendants. Fumigation is not *o successful as was hoped. Experiments have been made on the exact amount of air inhaled by various insects. Each species of insect displays a different reaction to poison gas. The cocoa moth is much more difficult to gas than the flour moth. Moreover, a moth culled Trichogramma, that attacks grain, withstands all known fumigants. This remarkable moth will live for seven days in a vacuum, and can exist for several years with no foil at all. This gives some Idea of what confronts man In his everlasting battle. against the insect world.