HORNTAIL BORER

Otago Daily Times, Issue 21774, 13 October 1932, Page 6

HORNTAIL BORER

IMPORTATION OF PARASITE INDICATIONS OF SUCCESS. (Per United Press Association.) , • . NELSON, October 12. Duflhg the last; few years the attention of those interested in -the conimer,cial production of -pine trees has been drawn to the activities .of tfic steel blue ‘horntail J&orer which is now well established in the Dominion. •Though it dops not damage vigorous trees, it is much too common to be discarded.as.of minor importance. The parasite of; the borer, being known to occur in England, Dr D. Miller, director of the entomological department of the Cawthron Institute,. arranged with the director of the Farnham Royal Parasite Laboratory for the parasite to be studied and supplies sent to New Zealand. This was quite a new departure in biological control in that it was the first attempt made to transport the padsite of a wood-boring insect from one country to another and establish it in a new environment. Several consignments of the parasite were sent to the Cawthron Institute, where the work has .been carried out as one of the major operations. Though many of the parasites perished before reaching maturity, a considerable number survived and many were liberated among borer-infested trees near Blenheim, Hannicr, and Moutere, while others were retained at the Cawthron Institute. That there was sonic possibility of the parasite succeeding in this country ’shown by the activities of the insect in locating the position of its victims in infested trees, prior to piercing the bark and laying its eggs.on the boring grubs. Whether this had been successfully accomplished or not, could not, however, ho practically ascertained, the parasitised borer being concealed within the timber. In consequence, a careful watch was kept for the emergence of adult parasites from trees in which the parasites were known to have laid their eggs. During the last week dr two these emergencies have been taking place in the insedory at the Cawthron Institute, and there is every reason to expect that the same process is taking place in the plantations at Blenheim, Hanmer, and , Moutere. The appearance of this first generation of the parasite to be ieared lit- New Zealand is 'one of the most important: developments in’ insect pest control during the year, and gives great promise of the successful establishment of the parasite and the subjection of the horntail borer in the Dominion.