Commercial Timbers


H. G. Richter and M. J. Dallwitz

Terminalia amazonia (Gmel.) Exell (Nargusta, amarillo)

Nomenclature etc. COMBRETACEAE. + T. guianensis Aubl. Trade and local names: nargusta, pardillo amarillo, amarillón. Not protected under CITES regulations.

Description based on 6 specimens. Tree. Geographic distribution: Mexico and Central America and tropical South America.

General. Growth ring boundaries distinct. Heartwood basically brown yellow green (yellowish olive to golden brown), with streaks. Sapwood colour similar to heartwood colour. Density 0.57–0.8 g/cm³.

Vessels. Wood diffuse-porous. Vessels in multiples. Average tangential vessel diameter 90–185 µm. Average number of vessels/mm² 6–15. Average vessel element length 349–625 µm. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 8–10 µm, vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Tyloses in vessels present.

Tracheids and fibres. Fibres of medium wall thickness. Average fibre length 1187–1732 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres septate and non-septate.

Axial parenchyma. Axial parenchyma banded. Axial parenchyma paratracheal. Paratracheal axial parenchyma aliform, or confluent. Aliform parenchyma lozenge. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 3–4.

Rays. Rays 12–15 per tangential mm, exclusively uniseriate. Rays composed of a single cell type (homocellular); homocellular ray cells procumbent.

Storied structures. Storied structure absent.

Mineral inclusions. Crystals present, prismatic or styloids or elongate, located in ray cells or axial parenchyma cells. Crystal-containing ray cells procumbent. Crystal-containing axial parenchyma cells chambered. Number of crystals per cell or chamber one. Silica not observed.

Physical and chemical tests. Heartwood not fluorescent. Water extract not fluorescent; basically colourless to brown or shade of brown. Ethanol extract fluorescent. Colour of ethanol extract colourless to brown or shade of brown.

Illustrations. • Macro images. Terminalia amazonia. Transverse. Radial. • Transverse section. Terminalia amazonia. • Tangential section. Terminalia amazonia. • Radial section. Terminalia amazonia. • Crystals in rays and axial parenchyma. Terminalia amazonia. Large styloid crystals in rays and axial parenchyma (insert); note also presence of septate fibres.

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: 25th June 2009.’.