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Nomenclature etc. LAURACEAE. 35 species from tropical Asia and the australo-pacific region. Trade and local names: huru (ID); bagaoring (PH); kyese (MM); chick dong (LA). Not protected under CITES regulations.
Description based on 35 specimens. Tree. Geographic distribution: India, Pakistan, Sri Lanka, Myanmar (Burma), Thailand, Laos, Vietnam, Cambodia, Indomalesia, Australia, New Zealand.
General. Growth ring boundaries distinct (demarcated by marginal parenchyma bands). Heartwood basically white or grey; with streaks or without streaks. Sapwood colour similar to heartwood colour, or distinct from heartwood colour. Density 0.45–0.65 g/cm³.
Vessels. Vessels present. Wood diffuse porous. Vessels arranged in no specific pattern, in multiples, commonly in short (2–3 vessels) radial rows. Vessel outline rounded. Average tangential vessel diameter 90–150–240 µm. Average number of vessels/mm² 3–12. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) (5–)7–11(–14) µm. Small intervessel pits (5–7 µm) only in B. tawa. Vessel-ray pits with reduced borders or apparently simple, rounded or angular, located throughout the ray. Helical thickenings absent. Tyloses present, thinwalled.
Tracheids and fibres. Fibres of medium wall thickness. Average fibre length 900–1200–1450 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered and distinctly bordered. Fibres non-septate.
Axial parenchyma. Axial parenchyma present, banded. Bands marginal (or seemingly marginal). Axial parenchyma bands much wider than rays. Bands fine and coarse. Apotracheal axial parenchyma diffuse and diffuse-in-aggregates. Paratracheal axial parenchyma vasicentric and aliform. Aliform parenchyma of the lozenge type. Axial parenchyma as strands. Average number of cells per strand: 2–4.
Rays. Rays 4–8 per tangential mm, multiseriate, (1–)2–4 cells wide. Rays of two distinct sizes, or of one size. Height of large rays up to 500 µm. Rays composed of two or more cell types (heterocellular). Heterocellular rays with square and upright cells restricted to marginal rows, mostly 1 marginal row of upright or square cells and mostly 2–4 marginal rows of upright or square cells. Sheath cells absent.
Storied structures. Storied structure absent.
Secretory structures. Oil and mucilage cells present and absent, associated with axial parenchyma, ray parenchyma, and fibres. Oil and/or mucilage cells can be absent in some species or specimens. Intercellular canals absent. Laticifers or tanniniferous tubes absent.
Cambial variants. Included phloem absent.
Mineral inclusions. Crystals present (in: B. assamica (syn.: B. praecox), B. erythrophloia, B. fordiana, B. gammieana, B. gemmiflora, B. glauca, B. intermedia, B. laevis, B. lucidula, B. maingayi, B. tawa, B. tsangii, B. undulata, B. wightii) or not observed, in other forms (usually very small: prismatic, tabletoid, spindle-shaped, splinters), located in ray cells and axial parenchyma cells. Crystal-containing ray cells upright and/or square and procumbent. Crystal-containing axial parenchyma cells not chambered. Number of crystals per cell or chamber more than one. Crystals in one cell or chamber of the same size, or of two distinct sizes. Silica present (silica observed in: B. albiramea, B. bancroftii, B. bullata, B. castrisinensis, B. dictyoneura, B. elliptica, B. madang, B. malaccensis, B. micrantha, B. obtusifolia, B. oligandra, B. peninsularis) or not observed, as grains and in aggregates; in rays cells, in axial parenchyma (rarely).
Physical and chemical tests. Heartwood not fluorescent. Water extract fluorescent; colour of water extract colourless to brown. Ethanol extract not fluorescent. Colour of ethanol extract colourless to brown. Froth test negative. Splinter burns to partial ash. Ash white to grey.
Illustrations. • Transverse section. Beilschmiedia albiramea. B. assamica. • Tangential section. Beilschmiedia obtusifolia. • Ray size; oil cell. rays of two distinct sizes (left); large idioblast (oil cell) associated with marginal parenchyma (right). Beilschmiedia assamica. • Radial section. Beilschmiedia obtusifolia. • Crystals. crystals of variable form and size in Beilschmiedia species. B. maingayi: fairly large and frequent. B. assamica: small and frequent. B. gammieana: small and infrequent. • Silica. silica deposits of variable form and size in Beilschmiedia species. left and bottom: large aggregates in ray cells of B. micrantha. small circular grains in B. bullata.
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’.
