Commercial Timbers


H. G. Richter and M. J. Dallwitz

Cordia trichotoma (Vell.) Arrab. ex Steudel (Peterevy)

Nomenclature etc. BORAGINACEAE. Trade and local names: peterevy,guajayvi hu (PY); peterebí, loro negro, peterebí hú, peterebí saiyú, loro amarillo, afata (AR); louro-pardo, louro, louro amarelo, louro-batata, louro-da-serra, peterebi, louro cascudo, cascudinho, louro do sul, louro mutamba(BR); piquana blanca (BO); laurel negro, laurel (EC). Not protected under CITES regulations.

Description based on 16 specimens. Tree. Geographic distribution: southern Brazil and temperate South America.

General. Growth ring boundaries distinct. Growth ring boundaries, if distinct, demarcated by often discontinuous marginal parenchyma bands (1–2 cell rows) and a local thickening of rays. Heartwood basically brown. Sapwood colour distinct from heartwood colour. Odour distinct (weakly aromatic). Density 0.78 g/cm³.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in no specific pattern, in multiples, commonly short (2–3 vessels) radial rows and in clusters. Vessel outline rounded. Two distinct vessel diameter classes absent. Average tangential vessel diameter 120–160 µm; diameter of vessel lumina: large. Average number of vessels/mm² 2–5; vessels per square millimetre very few. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 5–8 µm, small, vestured. Vessel-ray pits with distinct borders, similar to intervessel pits, of uniform size or type, of the same type in adjacent elements, located throughout the ray. Helical thickenings absent. Tyloses in vessels present, thinwalled. Other deposits in heartwood vessels present, light brown organic contents.

Tracheids and fibres. Vascular or vasicentric tracheids sporadic to absent. Fibres of medium wall thickness. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Helical thickenings absent. Fibres non-septate.

Axial parenchyma. Axial parenchyma present, banded. Axial parenchyma bands marginal (or seemingly marginal), fine, up to three cells wide. Axial parenchyma paratracheal. Paratracheal axial parenchyma vasicentric and confluent. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 2–4(–5). Unlignified parenchyma absent.

Rays. Rays present, 5 per tangential mm, multiseriate (also if only few), 4–5(–7) cells wide, of medium width (3–5 seriate). Rays with multiseriate portions as wide as uniseriate portions absent. Aggregate rays absent. Rays of one size. Height of large rays 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. Sheath cells present. Tile cells absent. Perforated ray cells absent. Disjunctive ray parenchyma end walls indistinct or absent.

Storied structures. Storied structure absent.

Secretory structures. Oil and mucilage cells absent. Intercellular canals absent. Laticifers or tanniniferous tubes absent.

Cambial variants. Included phloem absent. Other cambial variants absent.

Mineral inclusions. Crystals present, prismatic, located in ray cells. Crystal-containing ray cells upright and/or square and procumbent, upright and/or square ray cells not chambered. Number of crystals per cell or chamber one and more than one. Crystals in one cell or chamber of the same size and of two distinct sizes. Crystal containing cells of normal size. Cystoliths absent. Prismatic crystals also in sheath cells. Silica not observed.

Illustrations. • Transverse section. Cordia trichotoma. Note traumatic axial intercellular canals (TIC) forming a tangential band. TIC. • Tangential section. Cordia trichotoma. • Radial section. Cordia trichotoma.

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.’.