Crystals in woody stems

Abstract

Scanning electron microscopy has been used to examine the location and form of crystals in the stems of woody perennials. The results are discussed in relation to the effects of physical conditions and “impurities” upon crystal form. Infrared spectroscopy and X‐ray diffraction have been used to establish the chemical identity of the crystals in a number of species which were chosen so as to provide a wide variation in form. Those from Populus deltoides and Polyalthia sp. consisted of calcium carbonate; those from ten other species consisted of hydrated calcium oxalate. The infrared spectra of the crystals from Dracaena fragrans, Terminalia balerica, Goniothalamus sp. and Combretum verticillatum were strongly indicative of calcium oxalate monohydrate, but in the other cases the degree of hydration of the oxalate was uncertain. Copyright © 1973, Wiley Blackwell. All rights reserved