Understanding and using yield maps - an analytical tool for their interpretation

Yield mapping is increasingly used on combinable crops, but the agronomic q uestions about how the variability that it reveals should be managed remain largely unanswered. Yield maps are complex and often reveal patterns of va riability that change markedly from season to season. This raises questions as to how useful they really are. An approach to analysing sequences of yi eld maps is described, which aims to simplify their complexity by identifyi ng broad regions within which the season-to-season variation in yield is si milar. Such regions are likely to reflect the effects of similar Limiting f actors, and so may provide a basis for cost-effective investigations of the causes of variable yields and identification of an appropriate response.