FIGHTING THE LOCUST.

Auckland Star, Volume LXVI, Issue 29, 4 February 1935, Page 6

FIGHTING THE LOCUST.

Africa and AVestern Asia arc known to be the areas of the world's surface where the ravages of the locust are most destructive, and this year the infestation in the middle areas of the Cape is exceptionally severe (says "The Times"). Swarms have penetrated to within a hundred miles of Capetown, and fears are entertained that they may reach the fruit and wine areas in the south-west. It is generally agreed that "by far the most effective way to tackle the locust pest is to attack it at its source; and at the conference held in London last September it was resolved that the main object of research should be to delimit the outbreak areas, with a view to exterminating the immature insects in their homelands. Once the swarms, whether hoppers or flyers, have descended on the countryside the efforts ■of man can seldom materially restrict the volume of invasion. The South African Government is delivering its counter-attacks with resolute energy, and apparently not without success. Special trains are being driven through the invaded regions, in spite of the difficulty of getting the wheels to grip the slippery rails as they crush the insects on the line, and hose pipes spray the swarms on either eide of the track. The standard method of control is to epray the infected area with arsenite of Soda; but it is being found that when the same places are sprayed again and again the grass becomes poisoned and the stock which grazes on it dies. Moreover, the wild birds, who are the natural enemy of the locust, take the poison, and the destroyers are themselves destroyed. "Dusting" operations have been experimentally carried out by aeroplanes. It proved practicable to treat roosting swarms with the aeroplane flying at a height of approximately thirty yard's from the ground. Further tests seem, however, to be necessary before this method can be widely' adopted. It is in particular not yet determined what is the correct dose of poison to bo sprinkled. It must bo enough to kill the locusts, but so small as not to affect men and beasts. It is .nevertheless foreseen in South Africa that in the near future aerial combats may be fought between airmen and swarms on the wing.