Dillenia spp. (Simpoh, simpur)
Nomenclature etc. DILLENIACEAE. Wichtige Arten important species Dillenia excelsa, D. grandifolia, D. indica, D. philippinensis, D. papuana, D. pentagyna, D. pulchella, D. reticulata, D. salomonensis, D. schlechteri. Trade and local names: simpor (MAL); simpur, sempur (RI); katmon (RP); zinbyum, mai-masan (BUR); san (K); san, masan (T). Status of protection under CITES regulations: not protected.
Tree. Geographic distribution: Burma to Indomalesia.
General. Growth ring boundaries indistinct or absent. Heartwood basically brown to red purple, without streaks. Sapwood colour distinct from heartwood colour. Odour indistinct or absent. Basic specific gravity 0.54–0.88 g/cm³.
Vessels. Wood diffuse-porous. Vessels arranged in no specific pattern, exclusively solitary. Vessel outline rounded, or angular. Average tangential vessel diameter 110–240 µm. Average number of vessels/mm² 3–9. Perforation plates scalariform, with 5–40 bars. Intervessel pits scalariform or opposite, average diameter (vertical) 9–11 µm, not vestured. Intervessel pits rare, mostly restricted to overlapping vessel tips. Vessel-ray pits with reduced borders or apparently simple, different from intervessel pits, horizontal to vertical. Tyloses in vessels absent. Other deposits in heartwood vessels not observed.
Tracheids and fibres. Vascular or vasicentric tracheids sporadic to absent. Fibres of medium wall thickness to very thick-walled. Average fibre length 1700–3700 µm. Fibre pits mainly restricted to radial walls, distinctly bordered. Fibres non-septate.
Axial parenchyma. Axial parenchyma present, not banded. Axial parenchyma apotracheal. Apotracheal axial parenchyma diffuse, or diffuse-in-aggregates. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 4–8.
Rays. Rays present, 2–4 per tangential mm, multiseriate, also if only few, (1–)3–15(–20) cells wide. Rays with multiseriate portions as wide as uniseriate portions absent. Rays of two distinct sizes. Height of large rays commonly over 1000 µm. Rays composed of two or more cell types. Heterocellular rays square and upright cells restricted to marginal rows. Number of marginal rows of upright or square cells 2–4 to more than 4. Uniseriate rays composed exclusively of upright cells.
Storied structures. Storied structure absent.
Secretory structures. Intercellular canals absent.
Mineral inclusions. Crystals present, raphides, located in ray cells or axial parenchyma cells. Crystal-containing ray cells upright and/or square or procumbent. Crystal-containing axial parenchyma cells not chambered. Crystal containing cells enlarged (idioblasts). 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).