Wood of Giant Sequoia: Properties and Unique Characteristics1

Wood properties of giant sequoia (Sequoia gigantea [Lindl.] Decne.) were compared with those for other coniferous tree species. Wood properties such as specific gravity, various mechanical properties, extractive content, and decay resistance of young-growth giant sequoia are comparable to or more fa­ vorable than those of coast redwood (Sequoia sempervirens [D. Don] Endl.). It is recommended that giant sequoia be considered for planting stock in managed production forests to increase future supplies of wood having the characteristics so highly valued in coast redwood and other decay-resistant species. Giant sequoia (Sequoia gigantea [Lindl.] Decne.) is one of the oldest and certainly the largest living organism on earth. I have been studying giant sequoia and coast redwood (Sequoia sempervirens [D. Don] Endl.) since 1970. Although knowledge of both species is steadily improving, the focus has been on coast redwood, primarily because of its commercial importance. For this reason, correcting the many misleading generalizations about giant sequoia has been a slow and sometimes agonizing process. The wood from giant sequoia trees has had the repu­ tation of being very brash (brittle) and of little use for lumber products. This belief fails to distinguish differences between oldand young-growth trees, and it fails to recognize the wide range of wood products obtainable from forest trees besides lumber, e.g., particleboard, plywood, and paper (Piirto and Wilcox 1981). This paper has two objectives: First, to compare the wood properties of native grown giant sequoia to coast redwood, in­ cense cedar (Libocedrus decurrens Torn), white fir (Abies concolor [Gord. and Glend.] Lindl. ex Hildebr.) and western redcedar (Thuja plicata Donn). And, second, to emphasize the value of giant sequoia in both National Parks and in production forestry (e.g., plantations containing giant sequoia). It also highlights key points in the following subject areas: (1) general char­ acteristics and minute anatomy (2) physical and mechanical properties (3) chemical composition (4) natural decay resistance, and (5) utilization. Several excellent studies on the wood properties of giant se­ quoia grown outside of its native range have been and are being conducted in several foreign countries (Finogeev and Kuznecov 1969, Liubimirescu and others 1972, Knigge 1983, Knigge and Wenzel 1982, Knigge and others 1983). Presented at the Workshop on Management of Giant Sequoia, May 24-25, 1985, Reedley, California. Associate professor, California Polytechnic State University, San Luis