THE GRASS GRUB.

Stratford Evening Post, Volume XXIX, Issue 139, 4 August 1911, Page 2

THE GRASS GRUB.

the insect and its habits. The depredations of the (1 loaded , ass grim have been very severely jit, particular! v hi South and Midan’torlmry, during tlu> past season, .age areas of pastures have been .mOorcd practically valueless owing i the ravages of tne insect in c|Ut-s----iou, and in addition to attacking ..ics, the grub lias in some cases most completely - destroyed con suitable areas of autumn-sown grain tops. The loss in Canterbury alone said to have already amounted to vine thousands of pounds, and it is mt ended yet. _ _ Dr. Hilgendorf, biologist of Canterbury Agricultural College, in an inoresting interview with the ‘Press,'' gives a brief outline of the ife history of the grub. The grub, he ays, is tiie larva of a beetle, which i a native of New Zealand, ts scientific ppellation being “odontria Zealandi.i" ■ it is a cockchafer, and beings to tile same species as the iuropean cockchaler, though our ascot is a smaller one. The beetles merge generally about the first week a November, and for too next six reeks or so are busy laying eggs rnicli will provide for tne next genettion. A fortnight or so before Oili istaas all the beetles have finished their gg-laying, and by the time Christaas is passed most of them are dead. , go eggs they have laid usually hatch mt in December, but the grubs are very small, and tiic damage they do is nirdly noticeable until about May, by .vliicli time they have grown a good .leal, and eat proportionately more mod. If the season' is a mild and genial one, the grubs live about two aches below the surface of the soil, art if the season is wet and the temperature low, the gi übs bin row downvards to escape the rigours of the climate, and they consequently get be,ow their food region. If the food supply is good, and the grubs have been enabled to lay up ailficiont store of nutriment in their podics to act as a reserve to take them through their resting stage, they will pupate, that is, turn into a chrysalis, about October, and emerge is a beetle in November, thus completing their life cycle. But if the rood supply has been poor, and if they nave had to burrow deep to escape the ■old and wet and so nave got below ,bat portion of the soil that contains .heir food supply, then they do not pupate in October, but will hang on mtil a second season has passed, and lometimes even until a third. Thus .V will ho seen that a severe winter, .viiifi not perhaps killing many grubs, .\ ill prevent them turning into booties, and as the hectics, by laying eggs provide the increase, tne fact tliat few, if any , beetles emerge after a

severe season is a great check to the pest for a time, as it prevents the multiplication of the species. The fact chat few beetles emerge after a cold, vet season does not mean that the 'rubs have been killed.