RAGWORT WEED BORER.

Taranaki Daily News, 8 March 1924, Page 15

RAGWORT WEED BORER.

NEW KING COUNTRY GRUB: . ATTACKS AND KILLS PLANTS. A King Country correspondent writes: An unknown quantity has entered into the battle being waged against the spread of the ragwort weed, and though at present it appears to be on the side of the long-suffering settler, investigations have yet to show the full results of the new visitation. The unknown factor airpears to be a species of borer (entirely different from the leaf-eating caterpillar mentioned in a former article), which appears to eat its way up the centre of the stalk from the root, devouring the pith of the plant as it proceeds. The grub seems to have been first noticed in the King Country by Mr. C. P. Hugonin, of Waitete, who brought it under the notice of Mr. Mostyn Jones, chairman of the Te Kuiti Chamber of Commerce. The grub itself is apparently new to the district. It reaches an average size of about onequarter inch in length and is bluishgreen in appearance. Its effect on the plant is to leave the root in a state of dry-rot, and the weed attacked dies down completely. Mr. Mostyn Jones forwarded specimens of ragwort containing the borer to the Biological Department in Wellington, which later forwarded a very interesting reply dealing with the matter. Though it is not possible to name the larvae, It was announced as being the grub of some moth. The specimens forwarded are being reared to the adult stage in order to enable identification to be made. The Department regards the discovery as a most interesting one, and there is a possibility that the insect will do very valuable work in ragwortinfested areas; but its value cannot be decided until it has been found what other plants it feeds, as a number of weed-eating grubs are pests in relation to valuable plants. The Department is making further investigations and these will be announced later.

It is reported that the grub has been found in the Waitete, Pio Pio and disrtidts. _