Tilia spp. (Linde, lime, basswood)
Nomenclature etc. TILIACEAE. T. cordata Mill. = Winterlinde - Syn: T. parvifolia; T. platyphyllos Scop. = Sommerlinde - Syn: T. grandifolia; T. americana L.; T. glabra Vent.; Tilia spp. Trade and local names: Linde (D); lime tree (GB); tilleul (F); linden (NL); basswood, beetree, linn wahoo, wichup (USA).
Tree. Geographic distribution: Europe, excl. Mediterranean, Mediterranean incl. N. Africa and Middle East, temperate Asia, and North America.
General. Growth ring boundaries distinct. Heartwood basically white or grey to yellow white or grey to brown. Sapwood colour similar to heartwood colour. Basic specific gravity 0.32–0.49–0.56 g/cm³.
Vessels. Wood diffuse-porous. Vessels in multiples, commonly short (2–3 vessels) radial rows and in clusters. Vessel outline angular. Average tangential vessel diameter 70–90 µm. Average number of vessels/mm² 70–130. Average vessel element length 300–600 µm. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 4–7 µm. Vessel-ray pits with distinct borders, similar to intervessel pits. Crossfield pits considerably smaller (3–4 µm) than intervessel pits. Helical thickenings present, in narrow and wide vessel elements, throughout the body of vessel elements.
Tracheids and fibres. Fibres very thin-walled, or of medium wall thickness. Average fibre length 800–1100–1500 µm (Tilia americana). Fibre pits common in both radial and tangential walls, distinctly bordered. Fibres non-septate.
Axial parenchyma. Axial parenchyma banded. Axial parenchyma bands marginal (or seemingly marginal), fine, up to three cells wide. Axial parenchyma apotracheal. Apotracheal axial parenchyma diffuse and diffuse-in-aggregates. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 4.
Rays. Rays 7–10 per tangential mm, multiseriate, also if only few, 1–3–5 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. Sheath cells absent. Few heterocelular rays present, of no diagnostic significance.
Storied structures. Storied structure present, some rays storied, some not, axial parenchyma storied, vessel elements storied, fibres storied or not storied. Number of ray tiers per axial millimetre 2–3. Storied structure rather inconspicuous, often easier observed at the macroscopic than the microscopic level.
Mineral inclusions. Crystals (only T. americana) present or not observed, druses, located in ray cells. Crystal-containing ray cells procumbent. Number of crystals per cell or chamber one. Silica not observed.
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).