PRICKLY PEAR

Ellesmere Guardian, Volume LIV, Issue 22, 21 March 1933, Page 8

PRICKLY PEAR

3,000,000 ACRES RECLAIMED.

CACTOBLASTIS EFFECTIVE

By biological means, 80 per cent, of what was an almost impenetrable mass of prickly pear has been destroyed in Queensland, and from 50 to 60 per cent, in northern and northwestern New South Wales. In Queensland 1,250,000 acres formerly under pear have been re-selected for farming and 1,750,000 acres for grazing purposes.

Mr G. D. Ross, Under-Secretary of the Department of Agriculture, during an address to Rotarians, described a work which should rid Australia ultimately of one of her worst pests.

Since the first settlement Australia had suffered severely from the importation o& pests, Mr Ross said. He cited a modern instance of the thoughtlessness and carelessness frequently responsible. To advertise a moving picture, dart-shaped missilss, tipped at the ends with burrs so that they would stick in people's clothes, were circulated. Each burr contained 20 saeds of a very bad noxious weed grown in America. Although an assurance was given that boiling had destroyed the potency of the burrs, a simple germination test by the department proved it quite incorrect.

En route to Australia in 1788, Governor Phillip called at Brazil, whence he brought some prickly pear plants which were infested with cochineal. In those days soldiers wore scarlet uiforms, and the cochineal was required to provide the necessary dye. Apparently, the cochineal insects were lost in transit, and the pear became established in Australia without any controlling influence. A factor which helped its distribution was that because of its impenetrability several people living in the isolated regions of those days grew prickly pear to form hedges. A drought also aided its spread, Emus, driven from the western country in search of food, existed on the fruit of the prickly pear, and distributed the seeds over a wide area. By 1920, 60,000,000 acres, an area larger than Great Britain, was infested with prickly paar, and it was spreading at the rate of 1,000,000 acres per annum.

Cactoblastis had been introduced from America and had proved a remarkabla success. This insect lived on prickly pear, and very often carried bacterial diseases which helped to destroy it.