The presence of weeds which have developed resistance to chemical herbicides is a problem of rapidly growing importance in Australian agriculture. We present an optimal control model of herbicide resistance development in ryegrass, the weed for which resistance is most commonly reported. The...

Following the dismantling of a price-support program, a central bureaucracy is left with a commodity stockpile to dispose. It happened with wheat and feed grains in the U.S. in 1986 and wool in Australia in 1991. It soon may happen in Europe with grains, manufactured dairy products and other...

A biologically realistic model of crop yield response to herbicide application is presented. It includes functions for weed mortality from herbicide application and yield loss due to surviving weeds. The optimal herbicide rate and two types of decision thresholds are derived theoretically and...

A programming technique, utility-efficient programming, is developed for farm planning under risk. The objective function is the parametric sum of two parts of the utility function in which the degree of risk aversion varies systematically with the parameter. This technique has several...