Georgia is from Wanaka via the Waikato. She summarised archived lucerne yield data from Waikato, Taupo, Manawatu, Marlborough, Canterbury and Otago regions. The main aim of this dissertation was to determine whether lucerne yields at the ‘MaxClover’ grazing experiment established at Lincoln could be predicted from local weather data. The analysis of dry matter yield over six harvests per season identified two phases of growth, each influenced by mean air temperature, soil moisture or both. Analysis showed that accumulated thermal time (°Cd), potential soil moisture deficit (mm) and rainfall (mm) were able to be used to estimate lucerne production. The quantification of these relationships will allow farmers to predict the potential yield of their lucerne stand with the use of specific climatic data for their region and soil type. Prof. Derrick Moot supervised the work.