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| Commercial timbers |
Nomenclature etc. MYRTACEAE. Trade and local names: guabijú, guabiroba, guabijuzeiro (BR); arrayán, a. negro, guabira (AR); guayabilla, mato (BO); ivaviú (PY). Not protected under CITES regulations.
Description based on 1 specimen. Tree. Geographic distribution: tropical South America, southern Brazil, temperate South America.
General. Heartwood basically brown.
Vessels. Vessels present. Wood diffuse porous. Vessels arranged in no specific pattern, exclusively solitary. Average tangential vessel diameter 10–24–42 µm. Average number of vessels/mm² 105–137–179. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 5–7 µm (pits between vessels and tracheids). Vessel-ray pits with distinct borders, similar to intervessel pits. Helical thickenings absent.
Tracheids and fibres. Vascular or vasicentric tracheids commonly present. Fibres of medium wall thickness. Fibre pits common in both radial and tangential walls, distinctly bordered.
Axial parenchyma. Axial parenchyma banded. Axial parenchyma bands much wider than rays. Bands fine and coarse. Parenchyma bands 2–6 cells wide, sometimes discontinuous. Axial parenchyma apotracheal. Apotracheal axial parenchyma diffuse. Axial parenchyma as strands. Average number of cells per strand: 3–5.
Rays. Rays 15–18–21 per tangential mm, multiseriate, (1–)2(–3) cells wide. Height of large rays up to 500 µm, or commonly 500 to 1000 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. Disjunctive ray parenchyma end walls distinct.
Mineral inclusions. Crystals not observed. Long chains of prismatic crystals observed only at the periphery of traumatic tissues (when present). Silica not observed.
Illustrations. • Transverse section. • Tangential section. • Radial section.
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’.
