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Commercial timbers

H.G. Richter and M.J. Dallwitz

Ilex spp. (Holly, congonha)

Nomenclature etc. AQUIFOLIACEAE. I. amplifolia Rusby, I. amygdalifolia Rusby, I. anomala Hook. & Arn., I. boliviana Britton, I.laurina Kunth, I. petiolaris Benth.. Trade and local names: holly (US); algodón (CO); jaque blanco, j. negro (sAm). Not protected under CITES regulations.

Description based on 7 specimens. Tree. Geographic distribution: tropical South America.

General. Heartwood basically white or grey. Sapwood colour similar to heartwood colour. Density 0.52–0.62 g/cm³.

Vessels. Wood diffuse porous. Vessels in multiples, commonly in short (2–3 vessels) radial rows or in clusters. Vessel outline angular. Average tangential vessel diameter 56–92 µm. Average number of vessels/mm² 14–60. Average vessel element length 116–158 µm. Perforation plates scalariform, with 20–40 bars. Intervessel pits scalariform or opposite. Vessel-ray pits with distinct borders, similar to intervessel pits. Helical thickenings present, in narrow and wide vessel elements, throughout the body of vessel elements.

Tracheids and fibres. Fibres of medium wall thickness. Average fibre length 1809–2475 µm. Fibre pits common in both radial and tangential walls, distinctly bordered. Helical thickenings present.

Axial parenchyma. Axial parenchyma present. Axial parenchyma apotracheal. Apotracheal axial parenchyma diffuse. Axial parenchyma as strands. Average number of cells per strand: 5–8.

Rays. Rays 5–15 per tangential mm, multiseriate, 1–15 cells wide (multiseriate rays mostly 5–15 cells wide). Rays of two distinct sizes. Height of large rays commonly over 1000 µm. Rays composed of a single cell type (homocellular), or two or more cell types (heterocellular); homocellular ray cells procumbent, or square or upright. Heterocellular rays with square and upright cells restricted to marginal rows (square).

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

Physical and chemical tests. Heartwood not fluorescent. Water extract not fluorescent; colour of water extract colourless to brown. Ethanol extract not fluorescent. Colour of ethanol extract colourless to brown. Froth test positive.

Illustrations. • Transverse section. Ilex sp. • Tangential section. Ilex sp. • Radial section. Ilex sp. • Intervessel pits; spiral thickenings. Ilex aquifolium. opposite intervessel pitting (left); scalariform perforation plates and spiral thickenings in vessels (centre); spiral thickenings in fibres (right), present in some species, absent in others.


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’.

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