Water relations of tree crops. A comparison between Corsican pine and Douglas fir in South-East England.
Over 5 growing seasons, the annual cycle of water movement in semi-mature stands of Corsican pine and Douglas fir growing on deep porous soils of pH 4.0-4.3 was studied. Moisture tension in soil was measured by using gypsum resistance blocks and rainfall was equated with total evaporation and compared with values of open-water evaporation (E0) calculated from climatic records. Corsicanpine was found to dry the soil more deeply and intensely than Douglas fir and to use more water during the period of deficit. The causes of these differences are discussed.