THE PRICKLY PEAR

Dominion, Volume 11, Issue 90, 9 January 1918, Page 8

THE PRICKLY PEAR

AN AUSTRALIAN NUISANCE

DIFFICULT ECONOMIC

PROBLEM

There is a fortune awaiting tho man who can prove the comm«rcial value of the prickly pear, the seeds of which camo to, Australia from South America, when the firßt ships arrived. It has become a pest so great that tho Government of every State will give a big reward to tho man who can rid N the country of it economically,, or, better still, put it to commercial use. Early settlers nsed it as a hedge plant, and Mr. Froggart, the Government Entomologist, -states, on gootl authority, that the original centre of infestation in j\ 7 ow South Wales was from a.station garden n6ar Scono. Tho manager- grew hedges of prickly pear in all his paddocks with the idea that they would be a good food stand-by ill time of drought. A squatter from Queensland visited the station, and w«.i so struck by tho vivid green colour that he took cuttings of the pear back with him, and spread it far and wide on his holding on tho MoonDt River. _ Tho Queensland Government should hire a blasphemous poet to write bis epitab. Some years ago a French chemist evolved the idea of making mucilage from the leaves of tho prickly pear, which contains a quantity of gum. But when it came to turning out the product nicely bottled and labelled it was found that mucilage made from other products could run it off the markw It cost too much to produce, arid did not stick fast enough. Then the theory laid down by tl-.c Scone squatter that it was. gootl cattle food got abroad, and died hard There is 93 per cent, of water in prickly pear and 4tc 5 per cent, of fibre. The amount of nutriment is expressed by a mere cipher. Cattle get bloated' out on it and look prime. Milch Cows make no milk. Moreover, the prickles get in the beast's tongue and mouth, and it finds it almost impossible to chow succulent grass. ' Cattle become confirmed prickly pear topers and die. Another experiment was made lor producing potash from tho pear There is no plant food so much needed in Australia as potash, every ounce of which had in the past been brought from Germany. Scientists got together and decided to try to produce it, but it was found that the quantity of potash which could bo extracted from tho cactus is so infinitesimal that it ts not worth while treating it for the purYes, tho prickly pear' contains fibre, and great hopes were once expressed that tho problem of making ropes, string, paper, and other commodities would be solved by means of prickly pear. But the fibre has no staple, and what little there is of it disintegrates, into dust. There is no substance in it. . It was once suggested that the introduction of the cochineal insect would rid the country of the pest, and at tho same time introduce a profitable industry, for the cochineal insect is most useful for dye making. But it was found that the cochineal insect only lived on a certain kind of prickly pear, and the prickly pear so common in Australia is of no use to it. Then again the introduction of aniline dyes has 'almost' destroyed the cochineal industry, and little is used at'the present time.

There is still a big field for experiment in prickly pear, but most experimenters are devising means to get rid of it by the most economical means. Here again they are faced with difficulties.

The Agricultural Department of New South Wales has experimented extensively. The most successful eradicate is arsenite. of soda; but the cost is too great. Rollers and drags are also effectively used, and at Birriguy in the Moreo district one settler clears his land with a disc plough, to which he attaches a team of 20 bullocks. This land is good wfleat producing land, and it rjays better to clear it and get 10 bags of wheat to tho acre than to utilise tho pear for any other purpose.

At present experiments are being carried out in clearing the prickly pearinfested areas with arsenic-tri-chloride, which is the cheapest chemical yet used.

Mr. Froggatt suggests experiments with a very largo African land snail (Achatina fulico). The fact that this snail would only have a choico of prickly pear stems and gum-tree foliage would incline it to live on the more succulent cactus, and it would be quite happy under the sheltor of the cactus scrub, but would be unable to live in the hot sunlight. In five years tho progeny of a single snail would bo 10,930,442,400. Introduce 1000 snails, and thoy good-byo to tho prickly pear—and probably everything else, say the pessimists.