The use by farmers of futures contracts and other hedging instruments has been observed to be low in many situations, and this has sometimes seemed to be considered surprising or even mysterious. We propose that it is, in fact, readily understandable and consistent with rational decision making....

Paper removed at request of authors 08/03/07.

Most weed control decisions are made with the benefit of some information about weather conditions and actual weed densities. This study is an investigation of the value of adjusting weed control decisions in response to these types of information. For a specific example, it is found that the...

Use of lucerne (Medicago sativa L.) pastures in crop rotations has been proposed as a method to enhance weed management options for growers facing herbicide resistance in Western Australia. An existing model for analysing herbicide resistance in the important crop weed annual ryegrass (Lolium...

Bugs are an unavoidable aspect of mathematical programming (MP) modelling. In this paper we discuss the prevention and diagnosis of bugs in MP models. The topic is rarely addressed in the literature but is crucial to the success of modelling projects, especially for large models. We argue that...

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...