Commercial timbers

H. G. Richter and M. J. Dallwitz


Aspidostemon spp. (Longotra)

Nomenclature etc. LAURACEAE. Wichtige kommerziell genutzte Arten: important commercialized species:. Trade and local names: longotra (F, RM); longotra mena, longotra fotsy (RM). Status of protection under CITES regulations: not protected.

Description based on: 15 species/specimens. Tree. Geographic distribution: Madagascar & other islands (endemic).

General. Growth ring boundaries indistinct or absent. Heartwood basically brown to red. Sapwood colour distinct from heartwood colour. Basic specific gravity 0.75–0.9 g/cm³.

Vessels. Wood diffuse-porous. Vessels arranged in no specific pattern, in multiples, commonly short (2–3 vessels) radial rows to radial rows of 4 or more. Average tangential vessel diameter 80–140(–170) µm. Average tangential diameter of vessel lumina large. Average number of vessels/mm² 20–32. Vessels per square millimetre moderately numerous. Perforation plates simple or scalariform, with 2–10 bars. Scalariform perforations very few. Intervessel pits alternate, average diameter (vertical) 6–9 µm, medium. Pit cavities frequently with incrustations easily mistaken for vestures. Vessel-ray pits with reduced borders or apparently simple, horizontal to vertical. Helical thickenings rarely present or absent, only in narrow vessel elements, throughout the body of vessel elements. Tyloses in vessels present, thinwalled.

Tracheids and fibres. Fibres of medium wall thickness to very thick-walled. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres exclusively septate. Septate fibres evenly distributed. 1–3 septae per fibre.

Axial parenchyma. Axial parenchyma paratracheal. Paratracheal axial parenchyma scanty. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 3–4.

Rays. Rays 7–13 per tangential mm, multiseriate, also if only few, 2–3(–5) cells wide, 2–3 cells wide. Height of large rays up to 500 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 1.

Storied structures. Storied structure present, all rays storied, axial parenchyma storied, vessel elements storied, fibres storied. Arrangement of tiers regular (horizontal or straight) to irregular. Number of ray tiers per axial millimetre 3.

Secretory structures. Oil and mucilage cells present, cell type oil and mucilage cells are associated with axial parenchyma to fibres. Oil cells largely associated with rays (marginal rows), rarely with axial parenchyma or fibres.

Mineral inclusions. Crystals not observed. Silica not observed.

Physical and chemical tests. Heartwood not fluorescent.


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).

Index