Sapium spp. - New World species (Lechero)
Nomenclature etc. EUPHORBIACEAE. Sapium aucuparium, S. bolivianum, S. jamaicensis, S. laurocerasum, S. longifolium, S. macrocarpum, S. marmieri, S. montevidense, S. stylare, S. utile. Trade and local names: Pao de leite (BR); lecherón (RA); leche-leche (BOL); leche (JAM); bois de soie (RH); piniche, lechuga, lechero (C); manzanillo (Puerto Rico); curupicay (PY); lechillo, palo de leche (CR); cautahon blanco, kautsu masa (PE); curupi (ROU); lechero (YV); barbusco, caucho blanco, palo de leche (ECU).
Tree. Geographic distribution: Mexico and Central America, or Caribbean, or tropical South America, or southern Brazil, or temperate South America.
General. Heartwood basically white or grey. Sapwood colour similar to heartwood colour. Basic specific gravity 0.25–0.43 g/cm³.
Vessels. Wood diffuse-porous. Vessels arranged in no specific pattern, in multiples, commonly short (2–3 vessels) radial rows or radial rows of 4 or more. Average tangential vessel diameter 150–280 µm. Average number of vessels/mm² 2–10. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 10–14 µm. Vessel-ray pits with reduced borders or apparently simple, rounded or angular, of uniform size or type, located throughout the ray. Tyloses in vessels present, thinwalled.
Tracheids and fibres. Fibres very thin-walled, or of medium wall thickness. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres non-septate.
Axial parenchyma. Axial parenchyma banded. Axial parenchyma bands reticulate, fine, up to three cells wide. Axial parenchyma apotracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 3–4.
Rays. Rays 12–20 per tangential mm, exclusively uniseriate. Height of large rays commonly 500 to 1000 µm, or commonly over 1000 µm. Rays composed of two or more cell types. Heterocellular rays square and upright cells restricted to marginal rows. Number of marginal rows of upright or square cells 2–4, or more than 4. Some rays occasionally with biseriate central portion.
Storied structures. Storied structure absent.
Secretory structures. Intercellular canals absent. Laticifers or tanniniferous tubes present, or absent. No latex traces observed in New World species.
Mineral inclusions. Crystals present, prismatic, located in ray cells. Crystal-containing ray cells upright and/or square or procumbent. Number of crystals per cell or chamber one, or more than one. Crystals in one cell or chamber of two distinct sizes. Silica not observed. Silica mostly as small particles in asian species, as large aggregates often filling the entire cell lumen in african species.
Cite this publication as: H. G. Richter and M. J. Dallwitz (2000 onwards). 'Commercial timbers: descriptions, illustrations, identification, and information retrieval.' In English, French, German, and Spanish. Version: 4th May 2000. http://biodiversity.uno.edu/delta/.
Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993 onwards, 1995 onwards, 1998) should also be cited (see General references).