Water-Conduction in the Stems of Certain Conifers

Abstract

IN a laboratory study of the rate of flow of water through sapwood samples of Pseudotsuga taxifolia (Poir.) Britt., Pinus nigra Arnold, and P. radiata D. Don., the effective water-conducting areas were determined by using aqueous solutions of various dyes. It was observed that water-flow in the direction of the grain was restricted to the early wood, and that the late wood only became coloured, if at all, by later diffusion of dye, especially along wood rays. When acid fuchsin was used the wood became almost uniformly coloured due to the ready diffusion of this dye across the late wood, but when safranin was used the late wood remained unstained.