GRASS GRUB PEST.

Auckland Star, Volume LXIV, Issue 16, 20 January 1933, Page 2

GRASS GRUB PEST.

ARE BATS A REMEDY?

ENTOMOLOGIST'S VIEWS.

A member of the Morrinsville branch of the Farmers' Union advocated, at its meeting the other day, the introduc. tion- or the re-establishment of tha native bat, an insect-eating creature as a simple remedy for the destruction of the grass grub, which is becoming a pest in some districts, even so far south as Canterbury, where it is destroying p as . tures. When the matter was referred to Mr. C. E. Clarke, entomologist to the Auckland War Memorial Museum, to-day, he said that he thought the idea was a good one provided the bats could be introduced in sufficient numbers. He said that of the two species of native bats that were common enough when he was a boy, ono was now extinct, and the other was | rare. "The Australian bate, however' ; although they are different from our*'

would serve our purpose quite well" he said. "I have seen bats in Australia in the mountains taking insects on th® wing in the evening, and they do not seem to be particular as to what insects they take." He added-that these kts would make war on the mosquitoeß as \v:-ll as on the beetle, which produced' the grub. Our bats had vanished quickly in recent years owing to the increase in stoats, weasels, ferrets and wild cats. "You would be surprised at the number of cats that are going wild," said Mr. Clarke. "I noticed not a few wild cats in the Waipoua Forest and in other places I have visited. The bats live in hollow trees or caves, and fall an easy prey." The long-tailed bats were nowextinct, and the short-tailed bats rare. Feeds on Roots and Young Shoots.

Discussing the grub, Mr. Clarke said. I that it ate the roots of grass and also the young shoots. The beetles, which J produced the grub, fed on the petals of I flowers and sometimes on the leaves. "One when a friend was digging up a small piece of ground, he found from 30 to 35 grubs clinging to and feeding on the roots," said the entomologist "Such conditions are disastrous to pasI ture lands." The grub was very dej structive and appeared to be getting I worse. There were several species of the genus porana in New Zealand, of I which there were four or five common j varieties. These grubs turned into moths, which, unluckily, would not take tho bait of the naturalists —a mixture of rum and treacle. Bats were an excellent remedy to destroy them. The beetle was of the genus odontrla, of which there were 20 common species. The fields superintendent of the Agricultural Department, Mr. P. W. Smallfield, said that the grass grub did s great deal of harm, particularly in the dry season, when plants had less resistance to their attacks, and succumbed. "The grass grub is to be found all over New Zealand," he said, "but it is moet prevalent in the lighter types of soli, through which it can easily burrow to the roots of the plants." It was most prevalent in sttch districts as the Walkato and in Canterbury, in which latter district new grass, instead of being sown in autumn, was planted in spring, to evade, in gome degree, the attacks of this grub. Asked if any means had been adopted by tho Department to destroy the grub, Mi*. Siiiallfield 8 said that it Was under the serious consideration of tho entomologist of the plant research Station at Palmerston North.

Mr. T. Griffin, deputy-curator of the Museum, said that, while lie thought the bat would be a good means of destroying the pest, he did not See hO* they could introduce bats into tha country. "The bats," he said, "essentially take their food On the ttiiig, alive, and it would be a problem to know h&W to feed them when introducing them from another country." They would have to be introduced, as our native bats Were almost extinct. The insecteating bat, the most common variety new through the air with its mouth open for insects, like swallows* martins and swifts. He said that he had actually eeen a solid ball of insects in the mouth of one of these birds. There w<t9 another type of bat which fed on fruit and berries, and was found in the hotter countries, and was not insect-catiilg«