Cotton planted into stubble has shown many advantages over conventional planting practices, including: reducing soil erosion, reducing pesticide and nutrient movement, and improving soil condition (Waters and Sequeira 2000). However the main focus of the current research is to identify the potential benefits in insect pest management. There are many theories on why cotton is sprayed less when it is planted into wheat stubble, and these are currently being investigated. The two main ideas are that firstly, cereal stubble acts as a visual deterrent and obstruction to egg-laying heliothis moths and secondly that the stubble acts as a refuge for natural enemies which prey on or parasitise the heliothis eggs and young larvae.