|
| Commercial timbers |
Nomenclature etc. ARALIACEAE. Syn.: Didymopanax morototoni (Aubl.) Decne. & Planch. Trade and local names: amba'y guasu, amba'y, chipa rupa moroti (PY); amba'y guasu (AR); borracho, guitarrero (BO); caixeta, mandioqueira, morototó, marupauva falso, matatauba, mucututu, mandiocai, sambacuim, pixixica, cacheta (BR); candelero, roble, roble blanco, mirasol, chancarro blanco, mano de danta, pie de gallo, marota (MX); sun sun, cafetero, tinajero (VE); pata de gallina, yarumero, yagrumo (CO); platanillo, suntuch (EC); karohoro (GY); sacha-uva, anonilla (PE); guarumo macho (HN); pavo (PA). Not protected under CITES regulations.
Description based on 6 specimens. Tree. Geographic distribution: Mexico and Central America, Caribbean, tropical South America, southern Brazil, temperate South America.
General. Heartwood basically white or grey (pale brownish (dirty)); without streaks. Sapwood colour similar to heartwood colour. Odour indistinct or absent. Density 0.4–0.5 g/cm³.
Vessels. Wood diffuse porous. Vessels arranged in no specific pattern, in multiples, commonly in short (2–3 vessels) radial rows. Vessel outline angular. Two distinct vessel diameter classes absent. Average tangential vessel diameter 94–167 µm; diameter of vessels: medium and large. Average number of vessels/mm² 12–20; vessels per square millimetre few. Average vessel element length 860–1890 µm. Average vessel element length long. Perforation plates simple and scalariform (generally with few bars), with 1–5 bars. Scalariform perforation plates much less frequent than simple perforations. Intervessel pits alternate, average diameter (vertical) 10–12 µm ((vertical diameter; horizontally up to 30 µm)), pits vestured. Intervessel pits typically extended horizontally. Vessel-ray pits with reduced borders or apparently simple, different from intervessel pits, rounded or angular and horizontal to vertical, of the same type in adjacent elements, located throughout the ray. Helical thickenings absent. Tyloses absent. Other deposits present, organic deposits only sporadically.
Tracheids and fibres. Vascular or vasicentric tracheids sporadic to absent. Fibres very thin-walled, or of medium wall thickness. Average fibre length 1370–2750 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres exclusively septate, or septate and non-septate; scattered near vessels and rays.
Axial parenchyma. Axial parenchyma present, not banded. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma scanty. Axial parenchyma as strands. Average number of cells per strand: 3–10. Unlignified parenchyma absent.
Rays. Rays present, 3–5 per tangential mm, multiseriate, (2–)3–4(–5) 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.
Storied structures. Storied structure absent.
Secretory structures. Oil and mucilage cells absent. Intercellular canals present, non-traumatic origin, oriented radially.
Mineral inclusions. Crystals not observed. 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. • Tangential section. • Radial section. • Septate fibres; intercellular canals. radial intercellular canals (IC) and septate fibres. IC. IC.
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’.
