A MICROCOMPUTER SCHEDULING PROGRAM FOR SUPPLEMENTARY IRRIGATION

A real-time irrigation scheduling computer package for use on farms is described. The package comprises four models; a reference crop evapot ranspiration model, an actual evapotranspiration model, a soil water b alance model and an irrigation forecast model. The models used have be en shown to produce reliable estimates of the soil water balance, howe ver, the predictions are sensitive to the accuracy of the input data m easured on the farm. This paper summarises the experience of applying such a program to supplementary irrigation in the UK.