WHITE BUTTERFLY PEST

Taranaki Daily News, 31 March 1934, Page 11

WHITE BUTTERFLY PEST

PARASITES PROVE EXPENSIVE LIBERATION ON THE EAST COAST. A. AND P. ASSOCIATION SUBSIDY. Interested parties interviewed on Thursday on the subject of the white but^r “ fly see in the pest a serious menace tnat will defy destruction unless prompt measures are taken to combat its in* crease. One market gardener made it plain in no uncertain language that he considered it was the duty of the Department of Agriculture to take immediate and effective action instead of leaving the , sole preventive measures in the hands of juveniles competing for some prize ,or other given by a firm. It is a sorry state of affairs when the State has to leave it to business houses, who after all have an advertising, as well as a worthy preventive object m view, to do ite real work. These competitions, wonderful as the results have been in other parts, are but a drop in the ocean, A Westown correspondent has forwarded a turnip leaf which is absolutely riddled with holes, some as large as bullet perforations, eaten by what he terms the “notorious” white butterfly. The correspondent stated that the butterflies appeared to be spreading quickly around Westown and he was anxious to know if anything were being done to prevent their multiplication. His observations were that they preferred the swede to ragwort as ragwort growing in the vicinity of his swede crops still remained untouched. , Another party, purely a disinterested observer, pointed out the multiplicity of the white butterfly about Te Henui stream where from Devon Street to the Girls’ High School baths the growth and general vegetable on either side of the walk had been absolutely riddled. Every leaf was a skeleton, he said. On a railway journey to Wanganui white butterflies can be seen in paddocks and fields alongside the railway track for the whole of the journey, being particularly thick about Hawera and approaching An authority when questioned gave it as his opinion that the white butterflywas being blamed for much of the damage being done by the diamond-backed moth, an insect which by its comparative smallness carried on its destructive work unobserved. The query of one correspondent whether the Department of Agriculture was taking any steps in Taranaki to combat the white butterfly was referred to an officer of the department at New Plymouth. He stated that it was a matter for headquarters. The entomologist at the plant research department at Palmerston North was working on the problem of suitable parasites. Some had been released on the east coast, an A. and P. association having made a grant to the department to start combative movements. The expense was very heavy as the parasites had to be imported from England. In the first instance it would be necessary for some local body to take the lead and make some representations. The official emphasised that the department did not “buy” white butterflies. Scores of children with thousands of dead butterflies which they had captured had been worrying the local office of the department with offers of white butterflies. Mr. H. E. Blyde, president of the North Taranaki branch of the New Zealand Farmers’ Union, said he would bring the matter before the next executive meeting. The point in regard to parasites was to secure one which would not prove in the long run a bigger pest than that which it had been introduced to wipe out. ‘ HAWKE’S BAY CONTROL REPORTED. USE OF ENEMY PARASITES. By Telegraph—Press Association. Palmerston N., March 29. A statement that the white butterfly pest is being brought under control in Hawke’s. Bay was made by Mr. J. Muggeridge, Government entomologist at the plant research station. He added that the butterflies were not nearly so numerous there as last year. Out of 6000 butterfly pupae recently collected at random 70 per cent, were found to be parasitised. The methods adopted were the liberation of larval and pupal parasites. The first consignment of 10,000 of these insects from England was liberated in January and February last year in a concentrated locality of Hawke’s Bay. In the present season 200,000 larval parasites were liberated, : including some in the Manawatu district. A feature of the pupal parasites in Hawke’s Bay has been their amazing spread from the original point of distribution over hundreds of square miles. It is now established that a decrease has taken place in the number of pests where liberation of the pupal parasites has been carried out. The laval parasite is not yet showing effective results, but it is too early yet for comment. The main object now is to build up a huge supply of pupal parasites for wide distribution in the coming season.