The Effect of Prolonged Chilling on Water Movement and Radial Growth in Trees

Abstract

The woody shoots of young saplings of Fraxinus.excelsior and Acer Pseudo-platanus in pots were subjected to continuous cooling to about 2° C. during the growth season, with the result that radial growth was almost completely inhibited throughout the woody stem. The chilling did not adversely affect extension growth except that it was later in commencement and proceeded more slowly. If the temperature around the stem is lowered from 2° C. to 0° C., water conduction is cut down to such an extent as to cause wilting of the leafy shoots; turgidity is recovered when the temperature is again raised to 2° C. This wilting effect is discussed particularly in relation to the part played by living cells in the upward movement of water in the wood.