variation in resources. As a practical farmer, von Thunen knew that, in practice, the land-use pattern was modified not only by movement costs but also by the local availability of good soils, growing seasons, management ability, and so on. He produced a modified diagram in which the original rings (Figure 6.12a) were altered not by competing centres (Figure 6.12b) and cheaper transport routes (Figure 6.12c), but also by different land qualities (Figure 6.12d). A uesful example of how the classical von Thunen formulation can be modified be modified to apply to a specific area is provided by Rutherford et al.(1996) The assumptions of the model have been relaxed to accommodate three distoring factors: a coasline (Figure 6.13b), terrain oriented parallel to the coast(Figure 6.13c), and multiple instead of single markets(Figure 6.13d). Yet further relaxation to accommodate behavioural assumptions would be necessary to arrive at the actual land-use pattern for New South Wales(Figure 6.13e).