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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. 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 arranged in no specific pattern, in multiples, commonly in short (2–3 vessels) radial rows (predominantly) or in clusters. Vessel outline angular. Average tangential vessel diameter 40–70–120 µm. Vessels per square millimetre moderately numerous, or numerous. 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, different from intervessel pits, rounded or angular or horizontal to vertical, of the same type in adjacent elements or unilaterally compound and coarse (mostly arranged horizontally). Helical thickenings absent. Tyloses present, thinwalled.
Tracheids and fibres. Fibres very thin-walled to of medium wall thickness. Fibre pits mainly restricted to radial walls, distinctly bordered.
Axial parenchyma. Axial parenchyma present, banded. Bands marginal (or seemingly marginal). Bands fine. Axial parenchyma as strands. Average number of cells per strand: (4–)8–12.
Rays. Rays multiseriate, (1–)2–3(–4) cells wide (uniseriates rare). Height of large rays up to 500 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. Sheath cells absent.
Secretory structures. Oil and mucilage cells absent.
Mineral inclusions. Crystals not observed. Silica not observed.
Physical and chemical tests. Heartwood not fluorescent. Water extract fluorescent (greenish); colour of water extract colourless to brown. Ethanol extract fluorescent (yellow). Colour of ethanol extract colourless to brown. Splinter burns to full ash. Ash bright white.
Illustrations. • Macroscopic images. transverse (ca. 10x). radial (natural size). • Transverse section. • Tangential section. • Radial section. • Perforation plates, intervascular pits. scalariform perforation plates with few bars, opposite intervascular pits.
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: 9th April 2019. delta-intkey.com’.
