WEATHER VARIABILITY AND TEA YIELDS ON THE MAMBILLA PLATEAU, NIGERIA

Climate governs to a large extent the types of crop that could be. grown in a given area at a given time. With reference to tea production, the main climatic variables which influence the rates of shoot extension and ultimately the yield of tea arc temperature regimes, humidity, rainfall and evaporation (Carr, 1972; Squire and Calendar, 1981; Stephens and Carr, 1990a; Stephens el al., 1992). The effects of these variables on yield and its components have been well described and analysed in parts of tropical Africa (Stephens and Carr, 1989; Stephens el a/., 1992) and Sri Lanka (Fuchs, 1989), so that the ccophysiology of tea growth is fairly well known.