Experimental procedure in field trials on the control of grass grub (Costelytra zealandica(Wh.), Melolonthinae, Scarabaeidae) with insecticides, with particular reference to the sampling variance of larval populations

摘要

Data are presented on the variability of larval populations of the common grass grub (Costelytra zealandica(Wh.)) and a method described that has been used for field trials with insecticides. The degree of precision obtained in comparing the effects of treatments on grub population levels is examined.