Crystals in the wood of the genus Abies indigenous to Canada and the United States

Abstract

The scanty and conflicting literature on distribution and nature of crystals in the ray parenchyma of Abies is reviewed before results are presented from this study of 318 trees. Crystals of rhomboidal and elongated forms were regularly present, in descending order of frequency, in A. concolor, A. grandis, A. magnifica, A. bracteata, and A. procera. Crystals were deposited predominantly in marginal ray parenchyma cells which died prematurely within a critical zone of sapwood. Both forms of crystals were regularly lacking in A. amabilis, A. balsamea, A. fraseri, and A. lasiocarpa, although fairly frequently elongated types were found in certain samples of the latter species. A pattern of very infrequent crystal distribution was found in association with juvenile wood in a single mature A. grandis, and in seedlings or saplings of several species.A quantitative scale of crystal frequency was developed and its application to wood species identification demonstrated. The lack of crystals in A. amabilis is offered along with other evidence to suggest a relationship between this species and those of the series Lasiocarpae Franco.Chemical characterization by thin-layer chromatography, atomic absorption, and histochemical procedures confirmed the older supposition that both forms of ray parenchyma crystals were calcium oxalate.