A survey form asking the cost of weed control, the major weed problems and the herbicides used was sent to fifty two cotton growers from the seven major cotton areas of New South Wales.

The development of population dynamics models of heliothis populations in multi cropping systems required information on reproductive development, longevity and lifetime fecundity of adult female Heliothis in order to

A technique to identify the host crop of Heliothis moths by analysis of elemental content has been progressively developed over several seasons(CRC Project CS13L, Fin 1986).

The initial phase of the project was devoted to the selection and testing of analytical techniques for assessing total nitrogen and leaching losses, and gaseous losses of nitrogen by ammonia volatilization and denitri