Northern Australia, that is Australia north of 200s, is two regions with respect to crop production: (1) the Queensland coast (except Cape York) and adjacent hinterland, (2) the remainder. (1). The Queensland coast and hinterland has successfully sustained the production of sugar and tobacco for over 100 years and is closest to the major population centres of southern Australia. This region has seen the development of dams to supply the Mareeba and lower Burdekin areas, and there has been a steady diversification into horticulture, aquiculture, dairy and other crops. The success of tobacco since the 1940's is of interest because it required recognition of the ecological limitations of the natural environment and production changed from rain fed driving the wet season to irrigated daring the dry season. (2). The remainder of the Australian tropics is largely undeveloped for cropping or intensive animal production and prior to 1990 had a miserable record of failed developments. The production of cotton at the Ord during the 1960's and 1970's was a unique success in broad acre agriculture in this region until1974 when insect pests became uncontrollable, ie. &quote;heliothis went boo and we all run away&quote; Hearn (1996).