Quercus(r) spp. (Roteiche, red oak)
Nomenclature etc. FAGACEAE. Q. rubra - Syn.: Quercus borealis Michx. f. var. maxima (Marsh.) Ashe, Q. maxima (Marsh.) Ashe, Erythrobalanus rubra (L.) O.Schwarz; Q. falcata Michx.; Q. cerris L. Trade and local names: Roteiche (D); Q. rubra: Roteiche, Amerikanische Roteiche (D), Northern red oak (USA), American red oak (GB), chêne rouge (F), rood eiken (NL); Q. falcata: Southern red oak (USA); Q. cerris: Zerreiche (D).
Tree. Geographic distribution: North America, Europe, excl. Mediterranean, and temperate Asia (in Europe and Asia cultivated).
General. Growth ring boundaries distinct. Heartwood basically brown to red (pinkish brown) brown to yellow, without streaks. Sapwood colour distinct from heartwood colour. Basic specific gravity 0.48–0.66–0.87 g/cm³.
Vessels. Vessels present. Wood ring-porous. Vessels arranged in diagonal and/or radial pattern, exclusively solitary. Latewood vessels as opposed to white oak quite large, solitary and thick-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. Helical thickenings absent. Tyloses in vessels present (generally few tyloses), 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 (few). Fibres non-septate.
Axial parenchyma. Axial parenchyma predominantly 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 6–8.
Rays. Rays 9–14 per tangential mm (uniseriates, large rays 1–2/mm), multiseriate, also if only few, (5–)10–20–30 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 ray cells procumbent.
Mineral inclusions. Crystals present (few), prismatic, located in ray cells and axial parenchyma cells. Crystal-containing ray cells procumbent. Crystals in procumbent ray cells in radial alignment, or not in radial alignment. Crystal-containing axial parenchyma cells chambered. Number of crystals per cell or chamber one. Silica not observed.
Specific distinguishing properties. Red oak: latewood vessels as opposed to white oak quite large, solitary and thick-walled.
Miscellaneous. • Wood surface. Quercus rubra, radial plane. • Transverse ection, overview. Quercus falcata (red oak). • Transverse section, detail. Quercus falcata (red oak). • Tangential section. Quercus falcata (red oak). • Radial section. Quercus falcata (red 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).
