The paper describes experiments with FEARLUS, an agent-based model of land use change. The agents are satisficing (rather than optimizing) decision-makers. The paper focuses on the effects of varying agents' aspiration threshold : the economic return an agent requires from a parcel of land to persist with the current land use. If the threshold is not reached, the agent chooses a land use at random to apply to that parcel in the next year. It is shown that the optimum level for the aspiration threshold is affected by environmental heterogeneity and the level of return required to break even.