In all field trials, green unitrap bucket traps (International Pheromone Systems Ltd., Cheshire, UK) were suspended 1 -1.5 m above the pasture, in a random block design, with a minimum of 20 m between each trap and 20 m between each replicate. Each treatment was randomly assigned to a trapping station within each trapping row. Each trap contained a 2-cm killing strip of dog flea collar (Bayer, Germany), which contained 5% Diazinon insecticide as an active ingredient. All the blends of the synthetic compounds were applied to the large 'wells' of red rubber septa (West Pharmaceutical Services, Kearney, NE, USA) which were diluted in 150µL of n-hexane GR (Merck Ltd, New Zealand). The solvent was allowed to evaporate in a fume hood and the septa were stored in heat-sealed foil bags at -20°C until use. Pheromone impregnated septa were placed in the top compartment of the trap. In all field trials, five replicates for each treatment were tested. Traps were checked weekly in all trials, and moths were returned to the laboratory to be identified using a binocular microscope and the reference key by .