SCIENTIFIC RESEARCH.

Otago Witness, Issue 3801, 18 January 1927, Page 12

SCIENTIFIC RESEARCH.

DR TILLYARD’S INVESTI- - GATIONS. CONTROL OF NOXIOUS WEEDS. NELSON, January 11. Dr Tillyard, biologist of the Cawthron Institute, who has been on an extended visit to England, Europe, and America in the interests of scientific, research, returned to Nelson this morning. The results of his investigations have been embodied in a voluminous report which will be submitted to the Acting Prime Minister. The main report is confidential, and cannot be disclosed until released by the Minister. Dr Tillyard to-day said he was at liberty, however, to mention a few points connected with his tour, abroad. At the request' of the Prime Minister and the High Commissioner he extended his stay m England by an extra month to attend the Imperial Conference as New Zealand’s representative on the Research Committee. Dr Tillyard was the only. New Zealand represntative on that committee. He said his main investigations when abroad proceeded on various lines of entomological research in the shape chiefly of inquiries into the possibilities of the biological control of the blackberry and other noxious weeds, and that he had met •with considerable success in discovering insects which attacked the blackberry more or less efficiently. He was arranging for their introduction into New Zealand, under proper safeguards, of course. It very early became apparent to the investigator that such an enormous problem could not be attacked with a hope of solution without a large financial backing, so there was drawn up and submitted to the Enipire Marketing Board a scheme dealing with the question. The problem was of immense importance because other parts of the Empire were affected in a similar ■way to New Zealand. South Africa and Australia were experiencing a similar difficulty in respect to growths akin to. the noxious weeds of New Zealand. Those two countries had approved of and accepted the scheme put before them, and the final result had been an offer by the Empire Marketing Board of the sum of £2OOO a year for five years on condition that the New Zealand Government also gave £lOOO a year for five years, and the Cawthron Institute did the same, inis would mean a grant of £4OOO a year for five years, or £20,000 in all. This offer, Dr Tillyard further mentioned, was accepted by all concerned, the outome being a good workable scheme for the thorough testing of the possibilities or the control of blackberry, gorse, and . other noxious weeds by means of their insect enemies. The scheme, added the doctor, must be confined to insects, and fungoids must not be introduced on any account, as the risk in that connection of great damage bei*g done was -very serious. Another scheme submitted to the Empire Marketing Board was in the nature of a suggestion that Empire research into

the question of pasture efficiency should be undertaken. - New Zealanders are familiar with the recent discussions into the matter of deteriorated pastures. Investigations should be extended, it was urged, .to this Dominion, and the board agreed with the proposal. It offered £2OOO a year for two years on similar conditions to those outlined in connection . with noxious weeds research. The details of both schemes would require working out. Referring to the problem of the control of the earwig, Dr Tillyard said considerable advance had been made in regard to this question, and he had brought back with him a large supply of the puporia of the parasitic fly which attacked the earwig. He was hopeful of getting it acclimatised in New Zealand. A very interesting fact he discovered in England was that this parasitic fly had in its turn a secondary parasitic called the dibraehys —a little moth that attacked the puporia. This moth was a parasite of the wax moth, .which did so much damage in beehives. It had, therefore, been decided that the earwigs did the more good, and the dibraehys would have to be kept out. Dealing with the question of the eradication of gorse, Dr Tillyard said he had obtained large supplies of an insect which almost prevented it from seeding, and in England it was at present being successfully used in the solution of the problem.

Work had also been done in connection with the eradication of other weeds, such as ragwort and St. John’s wort, which were, in particular, very bad in Australia, and foxglove, which threatened to become a very poisonous weed in many parts <>f the Empire. The eradication of convulvulus had also been studied. It was the opinion of botanists that this plant was going to be one of the worst pests in the world during the next 50 years, and at present no satisfactory solution was in sight. Another large consignment of green lace wings, specially treated for the control of aphis blight on various trees, had been brought out, and if. it were possible to acclimatise them in New Zealand, Dr Tillyard thought that a lot of good would accrue. :

Generally speaking, Dr Tillyard affirmed that if the present line of modern research in .connection with the eradication of the weeds referred to were not successful it would be a pretty bad lookout, because there seemed no. other way of tackling the problem. Dr Tillyard found the institutions in England working on similar lines to the Cawthron Institute. He noticed particularly that the Rothamstead experimental station and Harpenden, near London, had developed immensely during the past six years.