ABSTRACT
The climatic contrast between the cool, wet upland regions in the north and west of Britain and the warm, dry lowland regions in the south and east is reflected in the British distribution patterns of many plants. Many climatic isolines run parallel to this line, and it is therefore generally supposed that climatic factors cause the south-west to north-east type of distribution limit’. The climate of Britain is extensively documented, and Gordon Manley provided a classic description, which is relevant to ecological studies at a geographical scale. Plants respond in diverse ways to the climate during all stages of their development from germination to the dispersal of propagules, and any response may be a cause, or a contributary cause, of a plant’s limit. Morphogenetic changes in leaf structure which affect growth rates have been demonstrated in a number of lowland species grown in upland sites, and the same effects have been reproduced in controlled environments at low temperatures.
