FOREST PEST

Timaru Herald, Volume CXLII, Issue 20613, 30 December 1936, Page 3

FOREST PEST

HORNTAIL BORER PARASITE SUCCESSFULLY ESTABLISHED Dr. Miller of the Cawthron Institute reports that the parasite that he imported for the control of the steelblue homtail borer of pine trees has now definitely become well established in plantations at Hanmer and the Moutere, and that there is little doubt that the same has taken place in other ’ocalities where the parasite was liberated but where no field observations have been possible this year. “The establishment of this parasite,” stated Dr. Miller, “is a matter of very great importance to all those interested in afforestation, since the horntail borer, though it infests weakened, or dying trees for the most part, renders useless many trees which could be otherwise utilised and at the same time reduces trees to a state favourable for the breeding of the European Barkbeetle which is a decided menace to the establishment of young plantations. Indeed, it has been found in New Zealand that the bark-beetle will destroy fully 30 per cent, of seedling trees planted in the vicinity of old stumps and trees infested by the beetle. “The success of the researches upon, and establishment of the horntail borer parasite is due to the ability of Mr A. F. Clark, Forest Entomologist, who handled the work during the several years he was associated with the Cawthron Institute. Unlike many insects, the horntail parasite presented outstanding difficulties demanding the development of special technique and which were successfully overcome by Mr Clark. “This is the first case in the history of biological control of insect pests, where a parasite for timber-boring insect has been successfully transported from one hemisphere to another and effectively established. “The supplies of the horntail borer parasite were secured for us from England by the Farnham Royal Laboratory. A year or two ago a film of this parasite at work was made in England by the Empire Marketing Board and exhibited in the theatres of New Zealand.