Quercus(w) spp. (Weißeiche, white oak)
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 (D), European oak (GB), European white oak (USA), Europees eiken (NL), farnia (I), roble (E); Q. robur: Stieleiche, Sommereiche (D); Q. petrea: Traubeneiche, Wintereiche, Spessarteiche (D), Chêne pédonculé (F); Q. grosseserrata: Japanische Eiche (D).
Tree. Geographic distribution: Europe, excl. Mediterranean, or Mediterranean incl. N. Africa and Middle East, or temperate Asia, or North America (Q. alba).
General. Growth ring boundaries distinct. Heartwood basically brown to yellow to white or grey. Sapwood colour distinct from heartwood colour. Basic specific gravity (0.39–)0.6–0.65(–0.93) g/cm³.
Vessels. Vessels present. Wood ring-porous. Vessels arranged in diagonal and/or radial pattern or dendritic pattern (rarely dendritic), in earlywood exclusively solitary and in multiples (in latewood), commonly short (2–3 vessels) radial rows and in clusters (only latewood). Latewood vessels as opposed to red oak very small, in multiples, and thin-walled; see also illustration of this character. 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 in vessels 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 mostly apotracheal and paratracheal. Apotracheal axial parenchyma diffuse, or diffuse-in-aggregates (aggregates in short tangential lines between rays). Paratracheal axial parenchyma scanty. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 4–8.
Rays. Rays 5–12 per tangential mm (uniseriate rays; large rays 1–2/mm), multiseriate, also if only few, (2–)10–30 cells wide. Rays of two distinct sizes. Height of large rays commonly over 1000 µm. Rays composed of a single cell type. 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.
Miscellaneous. • Wood surface. Quercus sp. (white oak). • Transverse section. Quercus petraea (white oak). • Transverse section. Quercus petraea (close-up). • Tangential section. Quercus stellata (white oak). • Radial section. Quercus stellata (white oak).
Cite this publication as: H. G. Richter and M. J. Dallwitz (2000 onwards). 'Commercial timbers: descriptions, illustrations, identification, and information retrieval.' In English, French, German, and Spanish. Version: 4th May 2000. http://biodiversity.uno.edu/delta/.
Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993 onwards, 1995 onwards, 1998) should also be cited (see General references).
