The interpretation of leaf‐drying curves

A theoretical expression for the rate of water loss through the surface of excised leaves has been derived so that curves fitted to experimental data can be used to infer physical properties of the leaves such as the solute concentration and the conductance for water vapour loss. The use of the equations is illustrated by reference to data from an experiment in which red spruce ( Picea rubens Sarg. ) and Norway spruce ( P. abies (L.) Karst.) seedlings were grown under five different regimes: outdoors (±50% shade), in a greenhouse (±50% shade) and in controlled‐environment chambers.