Mortality of Codling Moth Eggs and Young Larvae in an Integrated Control Orchard

Proof of insect predation by small arthropods is difficult to obtain under orchard conditions. The act of predation is seldom observed and unless some characteristic sign is left by the predator there is little chance of recognizing the species responsible. Many special techniques to study predation have been designed, but because they all have limitations it is still necessary to present circumstantial evidence in most predator-prey field studies. Perhaps the most common technique used is the limb or tree cage whereby both prey and suspected predators are released within the cage and observations made at regular intervals. This cage method, as well as the insecticidal check method of DeBach (1946) as modified by Lord (1956), the precipitin test (MacLellan (1954), West (1950)), the use of radioisotopes (Ahmed et al., (1954), Baldwin et al., (1955), MacLellan (1958b)), and others were considered for use in the present studies but were rejected because of particular limitations.