Commercial Timbers


H. G. Richter and M. J. Dallwitz

Liquidambar styraciflua L. (Red gum, sweet gum)

Nomenclature etc. HAMAMELIDACEAE. Similar species from southern Asia (1) and Asia Minor (2): Liquidambar formosana(1); Liquidambar orientalis(2). Trade and local names: red gum, sweet gum, ambar wood, tassel wood (US); Amberbaum, Satin-Nuss, (DE); estoraque, liquidambar, ocozotl (MX); satén (ES, cAm). Not protected under CITES regulations.

Tree. Geographic distribution: North America to Mexico and Central America.

General. Growth ring boundaries distinct. Heartwood basically brown to red, with streaks (black). Sapwood colour distinct from heartwood colour. Odour indistinct or absent. Density 0.44–0.55 g/cm³. Wood of commercial potential.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in no specific pattern, exclusively solitary or in multiples, commonly short (2–3 vessels) radial rows. Vessel outline angular. Two distinct vessel diameter classes absent. Average tangential vessel diameter 40–70 µm; diameter of vessel lumina: small to medium. Average number of vessels/mm² 100–170; vessels per square millimetre very numerous. Perforation plates scalariform, with 15–30 bars. Intervessel pits scalariform or opposite, average diameter (vertical) 6–9 µm, vestured. Vessel-ray pits with reduced borders or apparently simple, rounded or angular and horizontal to vertical, of two distinct sizes or types in the same ray cell, of the same type in adjacent elements, located throughout the ray. Helical thickenings present, in narrow and wide vessel elements, only in vessel element tails. Tyloses in vessels present, thinwalled.

Tracheids and fibres. Vascular or vasicentric tracheids sporadic to absent. Fibres very thin-walled to of medium wall thickness. Fibre pits common in both radial and tangential walls, distinctly bordered. Helical thickenings absent. Fibres non-septate.

Axial parenchyma. Axial parenchyma apotracheal, or paratracheal. Apotracheal axial parenchyma diffuse. Paratracheal axial parenchyma scanty. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 4–7.

Rays. Rays 9–13 per tangential mm, multiseriate (also if only few), 1–3 cells wide. Rays with multiseriate portions as wide as uniseriate portions absent. Aggregate rays absent. Rays of one size. Height of large rays up to 500 µm to commonly 500 to 1000 µm. Rays composed of two or more cell types (heterocellular). Heterocellular rays with square and upright cells restricted to marginal rows, mostly 1 marginal row of upright or square cells or mostly 2–4 marginal rows of upright or square cells. Sheath cells absent.

Storied structures. Storied structure absent.

Secretory structures. Oil and mucilage cells absent. Intercellular canals absent. Laticifers or tanniniferous tubes absent.

Cambial variants. Included phloem absent.

Mineral inclusions. Crystals present or not observed (prismatic crystals in upright/square and procumbent ray cells observed only in Liquidambar formosana), prismatic, located in ray cells. Crystal-containing ray cells upright and/or square or procumbent. Number of crystals per cell or chamber one. Silica not observed.

Physical and chemical tests. Heartwood not fluorescent.

Illustrations. • Transverse section. Liquidambar styraciflua. • Tangential section. Liquidambar styraciflua. • Radial section. Liquidambar styraciflua. • Miscellaneous. Liquidambar styraciflua. Note scalariform to opposite intervascular pitting and scalariform perforation plates. pits. plates. plates. • Crystals in rays. Liquidambar formosana. Large prismatic crystals present in rays of L. formosana (China, Taiwan) but absent in L. styraciflua (US, Mexico) and L. orientalis (Asia minor).

The interactive key allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting specified attributes, summaries of attributes within groups of taxa, and geographical distribution.

Cite this publication as: ‘Richter, H.G., and Dallwitz, M.J. 2000 onwards. Commercial timbers: descriptions, illustrations, identification, and information retrieval. In English, French, German, Portuguese, and Spanish. Version: 25th June 2009.’.