Insecticide application to control heIiothis on cotton is rapidly becoming a major production cost for field crops, particularly cotton, in central Queensland (CQ). Chemical protection of cotton crops is frequently required for more than 3/4 of the season. The intensive use of insecticides for heliothis control in cotton has led to an alarming rise in levels of resistance to many currently used insecticides (Fitt 1994, Gunning 1996). Insecticidal control of heliothis now costs many cotton growers in CQ in excess of $700/ha per season