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| Commercial timbers |
Nomenclature etc. FAGACEAE. Q. robur L. (Syn.: Q. pendunculata Ehrh.); Q. petrea (Mattuscka) Liebl. (Syn.: Q. sessiliflora Salisb.); Q. grosseserrata Bl. ( Syn.: Q. crispula Bl., Q. mongolica Fisch. ex Turcz. var. grosseserrata (Bl.) Rehd. & Wils.; Q. alba L., Q. muehlenbergii Engelm. Trade and local names: Weißeiche (DE), European oak (GB), European white oak (US), Europees eiken (NL), farnia (IT), roble (ES); Q. robur: Stieleiche, Sommereiche (DE); Q. petrea: Traubeneiche, Wintereiche, Spessarteiche (DE), Chêne pédonculé (FR); Q. grosseserrata: Japanische Eiche (DE). Not protected under CITES regulations, or listed in CITES Annex III (the only protected species: Quercus mongolica Fisch. ex Ledeb.).
Tree. Geographic distribution: Europe, excl. Mediterranean, Mediterranean incl. N. Africa and Middle East, temperate Asia, North America (Q. alba).
General. Growth ring boundaries distinct. Heartwood basically brown to yellow to white or grey. Sapwood colour distinct from heartwood colour. Density (0.39–)0.6–0.65(–0.93) g/cm³.
Vessels. Vessels present. Wood ring porous. Vessels arranged in a diagonal and/or radial pattern and a dendritic pattern (rarely dendritic), in earlywood exclusively solitary and in multiples (in latewood), commonly in short (2–3 vessels) radial rows and in clusters (only latewood). Latewood vessels very small, often in multiples, and thin-walled. Average tangential vessel diameter 130–290–420 µm. Perforation plates simple. Intervessel pits alternate. Vessel-ray pits with reduced borders or apparently simple, rounded or angular to horizontal to vertical (mostly vertical). Helical thickenings absent. Tyloses present (very frequent), thinwalled.
Tracheids and fibres. Vascular or vasicentric tracheids commonly present. Fibres of medium wall thickness. Average fibre length 280–880–1600 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered or distinctly bordered. Fibres non-septate.
Axial parenchyma. Axial parenchyma present. Axial parenchyma apotracheal, or paratracheal (in short tangential lines between rays). Apotracheal axial parenchyma mostly diffuse and diffuse-in-aggregates. Paratracheal axial parenchyma scanty. Axial parenchyma as strands. Average number of cells per strand: 4–8.
Rays. Rays 5–12 per tangential mm (only uniseriate rays; large ones 1–2/mm), multiseriate, (2–)10–30 cells wide. Aggregate rays absent. Rays of two distinct sizes. Height of large rays commonly over 1000 µm. Rays composed of a single cell type (homocellular); homocellular ray cells procumbent.
Mineral inclusions. Crystals present (rare), prismatic, located in ray cells and axial parenchyma cells. Crystal-containing ray cells procumbent. Crystals in procumbent ray cells not in radial alignment. Crystal-containing axial parenchyma cells chambered. Number of crystals per cell or chamber one. Silica not observed.
Specific distinguishing properties. White oak: latewood vessels as opposed to red oak very small, in multiples, and thin-walled.
Illustrations. • Macroscopic images. Quercus petraea. transverse (ca. 10x). radial (natural size). • Transverse section. Quercus petraea. • Tangential section. Quercus alba. • Radial section. Quercus petraea.
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’.
