Grass Grubs.

Hokitika Guardian, 30 October 1922, Page 4

Grass Grubs.

A PARASITE FROM AUSTRALIA X FI,SON. Oct LAI. Tho biological deptrrtment of the Cawthron lnsitute has just received from Australia a valuable consignment of flower wasps parasitic on grass grubs. Tbe.se insects are solitary wasps which do not make a nest and do not sting. The male is a small dark brown insect which frequents flowers in sear<'h of nectar, and the female is a wingless insect rather like a big ant. which burrows underground in search of grass grubs. When she finds one she lavs an egg on it, from which the re ha tele's a parasitic wasp grub, which proceeds to devour the grass grub entirely. These wasp grubs have no other food than grass grubs, to that the only problem to be solved is whether they will become aeelimatisod to lheir new conditions and line! the New Zealand grass grubs as much to their taste as the Australian species.

Tiles,- wasps will he kept nuclei strict control in the Cawthron Institute inseclariuni until such time as

their benefit to New Zealand is definitely proved. In order to give them an opportunity to attack New Zealand grass grubs freely, a large quantity of these grubs is required, and J)r Tillyary is asking Nelson people to send in consignments ol them with the least possible.delay, Each fern ile wasp is capable of parasitising a very large number of grass grubs, and as there are nearly forty pairs ol wasps in the consignment it will he seen that a very large number ol grass grubs will he required. The experiment! should he ol special interest to strawberry growers, as the imported wasp does valuable work in keeping the Sydney strawberry gardens free of a very troublesome pest, and it is hoped that it may ha able In ! do similar work in New Zealand.