Palm ?Wood? I. Anatomical aspects

Abstract

The “wood” of palms consists of primary vascular bundles imbedded in a parenchymatous ground tissue. The texture and hardness of a palm stem or petiole depend largely upon the distribution of vascular bundles and the amount of sclerenchyma present. The sieve elements are structurally similar to those in other angiosperms. However, in palms the sieve elements are long-lived, unlike those in most dicotyledons and gymnosperms. Metaxylem tracheary elements vary in their morphology depending on the organ and/or species in which they occur. Scanning electron microscopy observations indicate that the distinction between tracheids and vessels is not sharp but is a matter of degree. The fibers usually have a well developed secondary wall with a characteristically mulilayered appearance. There are indications that the protoplast of these cells continues to lay down secondary walls over a long period. Fibers are commonly associated with silica-containing cells, the stegmata.