Conventional linear models of research and extension, based on simplistic assumptions of diffusion, adoption and technology transfer, have been found wanting, particularly in complex and diverse agroecological settings, such as the grasslands of the world, where issues of sustainability and integrated resource management are central. This paper explores the relationships between different sourc...

This paper describes a Tropical Pasture Simulator. This is a simple mechanistic model representing the growth of vegetative tropical pastures under rotational or continuous grazing with responses to N fertiliser, temperature and irradiance that can be used as a tool to study management options for the development of sustainable grazing systems. The model was derived as an adaptation of the `Hur...

An outline is given of some of the main factors and interactions involved in the development of ryegrass staggers viz: pasture structure, neurotoxin distribution within the pasture, and livestock feeding behaviour. Because neurotoxicity is mainly associated with ryegrass leaf sheath the aim of control measures is to minimise ingestion of this component when it is toxic. This can best be achieve...