A VEGETABLE TERROR.
T is generally known that in the rich and warm lands of
the North of New South Wales and South and Central Queensland one of the worst pests is a vegetable, the prickly pear, Opuntia. Originally introduced as a pretty flowering hardy shrub, it was taken into favour as a hedge plant, and so long as its growth and spread were checked by man's supervision it never assumed the character of a public enemy. But like so many imported pests, vegetable like the lantana and the Bath- urst burr, which is a South American weed introduced with horses, or animal like the rabbit and the fox, it only needed neglect to develop serious consequences. In the klundly climate of these lauds, in a genial soil, and with few or none to watch or to stay its gradual invasion of new acres yearly, its progress was rapid. Prickly pear is of many varieties. In the beautiful Botanic Gardens at Sydney the learned Curator, Mr. J. H. Maiden, F.B.S., one of the world's authorities upon Australian botany, has a large bed where he cultivates some hundreds of varieties of this cactus. It is his hope that one day by means of hybridizing and other resources of the modern plant-wizard he may succeed in developing a useful, or at least a spineless and harmless, variety of the opuntia. I have myself seen and heard elderly gentlemen of the most evident respectability and substance, but of the paatoralist profession, almost inarticulate with rage and dismay at the scientific notion of breeding and in- breeding of this hateful variety. Is it not enough, they say, that millions of acres of land, some of it the richest we have in Queensland and in New South Wales, are so densely overgrown
with this pest that a rabbit or a snake can hardly force its way into it, and where we who are neighbours are put to yearly expense to keep the curse from spreading upon us, without spending public money in making a raree-show of this devilish thing ? In the clubs of Macquarie Street, Sydney, many a heated argument has proceeded upon this vagary of the scientific mind, and many a stiff whisky-and-soda has been necessary to restore the mental poise of sound old graziers disturbed by these silly notions of city visionaries.
For while the scientific botanist or entomologist slowly sought by study of his subject, and endless experiment with parasite insects and with disease or with variations induced by in-breed- ing, to cope with the pest, and either limit its increase or turn it to some profitable use, the vegetable itself, heedless of all the scientific work, went on gathering to itself new tracts-of grazing and farming lands. Year after year, not imperceptibly but little remarked because the regions of its infestation were remote from the ken of the official and newspaper world, the prickly pear possessed itself of miles of new territory. It grew from frag- ments of the parent shrub carried by flood or other accident, or from seeds swallowed by birds and voided many miles away. Beginning as a low and insignificant shrub, apparently harmless and in its season crowned with yellow flowers, to be succeeded by a small fig-like fruit, it flourished upwards and all around till it was a mass of fleshy stems with flat leaves, the whole several feet in height and many feet in circumference, thickly spread with thorns varying from hairs to pins in size, but all vicious. Its thorny habit not less than its thick growth made it impenetrable. Everything avoided it. It was not edible, and it was not in any degree useful. Such was the pest that, spreading from neglected gardens and hedges in the coastal districts, extended faster and ever faster inland until now it covers some millions of sores of country in New South Wales, and even more in Queensland. Its tenacity of life is almost unbelievable. Dug out in gardens and heaped up loosely for burning as soon as dry, it is found to be alive and ready in scores of places to resume its growth. I have seen a piece of prickly pear which in the process of digging out on a farm on the Darling Downs in Queensland had been casually caught on a fence-post. There it had hung for weeks blown about by the winds, dried by the sun, without any moisture other than the rain and the dew, and with no context with soil, and every scrap of the thing was not merely alive but growing.
Such is the evil growth with which Lands Ministers, scientific men, the Federal Bureau of Science and Industry, commercial experimentalists, and numbers of farmers and graziers in these two States are grappling. The Legislatures of Queensland and New South Wales have had to provide a new tenure for prickly peas lands, not so much to gain a revenue from them as to get them under human control and supervision. Endless processes of poisoning have been tried, but in the end it has been found that the cost was too great. The Bureau of Science and In- dustry in Melbourne believes that in insect parasites the most practicable form of destruction will be found. Practical men scorn the idea of pitting the cochineal insect or other " bug " against this unceasing invasion of a plant which can thrive in any soil and in any variation of season, wet or dry, and which cannot be killed by any less drastic measures than digging out, and when dry burning to ashes with the help of bonfires of wood and boughs. Just before the war the Queensland Government had an experimental section under trial with a trained scientific woman in charge to attempt the destruction of the pear by poison spray of an arsenious nature. Mr. Joseph Campbell, of North Queensland, has been at work in the endeavour to turn the fibres of the plant to account in paper-making and otherwise, but without any notable success. Mr. Maiden has been trying to evolve some method of dethorning the plant so that its fleshy matter might be available for stock in time of drought. Here again no appreciable success has followed. In short, we are up against a vegetable pest of incredible tenacity of life, of rapid spread, already the invader of millions of acres of the soil, and, so far as can at present be seen, of a total uselessness for any commercial purpose whatever.
Upon this gloomy prospect a ray of light is thrown by a Report issued on May 14th by Mr. W. G. Ashford, Minister for Lands in New South Wales, and himself a practical farmer of New England. Under his orders a gang of returned soldiers has been employed at Wangan, a spot in the Pilliga scrub in the North-West of New South Wales, which had been designed for settlement but was menaced by the spread of prickly pear,
Mr. Roberts, an American who had been at work on the problem in Queensland, and had abandoned the task there owing to the arsenious-soda spray used in atomizers not being a commercial proposition, had devised an improved pear poison. But the atomizers proved the difficulty. Experiments in collaboration with Mr. Roberts proceeded, and now, we are told in the official Report published recently, "The Departmental officers in charge have no hesitation in asserting that a means of destruction has been found which will certainly destroy the pear and at a cost far below that of any other method. About two hundred acres, a large part of which Is heavily infested, have been treated in this locality, with very satisfactory results. On experimental one-acre blocks very heavy pear growth of an average height of four feet was found, two weeks after spraying, to be well killed. The cost worked out at 30s. per acre for poison, the application of which occupied two men for forty-five minutes. A light spraying of the leaves only is necessary to kill, the circulation carrying the poison to the bulb. It is unnecessary to spray the stems owing to the efficiency of the atomizers. This is contrary to previous ideas, and enables a considerable saving of poison. It has also been proven that in treating with this poison, the pear should not be slashed or broken, as this destroys the circulation. The fruit falls off sprayed pear, and shrivels, the seeds turning to dust. Cattle have been observed to eat the pear in a wilted state about three days after poisoning, and without ill effects. Soft grasses that grew up through the dead pear were also eaten by stock without detriment to their health."
So far good ; but when we add to the 30s. per acre for poison the wages or the keep of the men employed on the job, cost of supervision, and all the numerous etceteras of a Government undertaking, it may prove that this experiment, like so many others, is successful in killing the pest but that the cost is pro- hibitive. However, a further experiment is to be made. The work of destruction of about 330 acres of pest pear, a bad seed-bed upon the Dartbrook Estate, near Aberdeen, which is being subdivided for returned soldiers, is to be undertaken by the Lands Department. The infested part is good land, adjacent to the' railway, and in its present condition is valueless. In any case, there must be found a check to this pest, which if let alone will turn whole sections of the best portions of these Northern States into worse than a wilderness, a perpetual
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