Precision irrigation is still in its infancy both in Australia and internationally. Despite the widespread promotion and adoption of precision agriculture in dry land cropping systems, the concept of precision irrigation or irrigation as a component of precision agricultural systems has not been widely canvassed nor its potential evaluated. This report is the outcome from a NPSI funded review of relevant irrigation research, existing technologies and the use of precision irrigation. It includes an assessment of the role of current irrigation application technologies in precision irrigation, as well as variable rate applications, adaptive control and the sensing and decision support requirements. The review also provides a framework to guide research and development of precision irrigation and its associated sensing, control, and decision support technologies.

The aim of the review was to detail the current state of the art of precision irrigation, including:

* an agreed conceptualisation and definition of precision irrigation,

* conceptualisation of how precision irrigation might be implemented for each of the current

irrigation application systems (sprinkler surface and micro), including as appropriate the

sensing, control and decision support requirements,

* identification of opportunities for and potential benefits from precision irrigation,

 identification of current research in precision irrigation and more particularly a clear

direction for future research in precision irrigation, and

* development of a series of case studies where precision irrigation is being implemented in

whole or part.

It is significant that no systems were identified in this country that could truly be classified as precision irrigation systems. However research is active in a number of areas relevant to precision irrigation and many of the component tools and technologies have been or are being developed. Examples of these are illustrated in the case studies included throughout the review and include:

* use of management zones in horticulture,

* automation of surface irrigation,

* real-time optimisation of surface irrigation,

* spatially varied applications from centre pivot and lateral move machines,

* vision sensing of crop attributes, and

* irrigation scheduling using remotely sensed crop factors.