An estimate of the net difference in yield of apple orchards in northern and in Southern Europe attributable to climate differences; with notes upon the economic significance of superiority in yield

Applying the economic concept of efficiency to the physiological behaviour of higher plants leads to a conclusion that deciduous fruiting trees in a Mediterranean location do not profit from their environment to the extent climatic parameters would suggest. The potential yield of commercial apple orchards in southern Europe is postulated to be less than 50% greater than on good sites in northern Europe, whereas some climatic parameters differ by 60 %. Given a constant proportional superiority for the south, the absolute gain over the north in physical yield will increase as the skill of the grower increases: it does not follow, however, that in practice as average levels of skill increase, southern growers will find their competitive advantage over northern growers thereby improved.