Commercial Timbers


H. G. Richter and M. J. Dallwitz

Liriodendron tulipifera L. (Whitewood)

Nomenclature etc. MAGNOLIACEAE. Trade and local names: Amerikanisches Whitewood (D); American Whitewood, canary (white-) wood (US); further (somewhat misleading) names: tulip wood, tulip poplar, yellow poplar. Not protected under CITES regulations.

Tree. Geographic distribution: North America (not in the extreme northerly and southeasterly parts).

General. Growth ring boundaries distinct. Growth ring boundaries demarcated by marginal parenchyma bands and noded rays. Heartwood basically yellow to green to brown (darkening to olive-brown), mostly without streaks (rarely with dark stripes = 'Calico poplar'). Sapwood colour distinct from heartwood colour. Density 0.4–0.5 g/cm³.

Vessels. Vessels present. Wood diffuse-porous. Vessels in multiples, commonly short (2–3 vessels) radial rows and in clusters (predominantly in radial groups). Vessel outline angular. Average tangential vessel diameter 40–70–120 µm. Perforation plates scalariform, with 3–5–10 bars. Intervessel pits scalariform to opposite, average diameter (vertical) 10–11 µm. Vessel-ray pits with reduced borders or apparently simple, horizontal to vertical, of the same type in adjacent elements or unilaterally compound and coarse. Compound pits mostly arranged horizontally. Helical thickenings absent. Tyloses in vessels present, thinwalled.

Tracheids and fibres. Fibres very thin-walled and of medium wall thickness. Fibre pits mainly restricted to radial walls, distinctly bordered. Fibres non-septate.

Axial parenchyma. Axial parenchyma present, banded. Axial parenchyma bands marginal (or seemingly marginal), fine, up to three cells wide. Axial parenchyma as strands. Average number of cells per axial parenchyma strand (4–)8–12.

Rays. Rays multiseriate (also if only few), (1–)2–3(–4) cells wide (uniseriates rare). 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.

Secretory structures. Oil and mucilage cells absent.

Mineral inclusions. Crystals not observed. Silica not observed.

Illustrations. • Macro images. Liriodendron tulipifera. Transverse. Radial. • Transverse section. Liriodendron tulipifera. • Tangential section. Liriodendron tulipifera. • Radial section. Liriodendron tulipifera.

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.’.