Commercial timbers

H. G. Richter and M. J. Dallwitz


Chorisia speciosa St. Hil.(samu'u)

Nomenclature etc. BOMBACACEAE. Trade and local names: samu'u, palo borracho (PY); paneira, paneira-branca, paina de seda, barriguda, arvore-de-paina (BR); paneira (USA). Status of protection under CITES regulations: not protected.

Description based on: 2 specimens. Tree. Geographic distribution: temperate South America.

General. Growth ring boundaries distinct, growth ring limits demarcated by bands of thicker walled fibres and thickened rays. Basic specific gravity 0.27 g/cm³.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in no specific pattern, in multiples, commonly short (2–3 vessels) radial rows. Vessel outline rounded. Two distinct vessel diameter classes absent. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 12–16 µm, large, not vestured. Vessel-ray pits with reduced borders or apparently simple, different from intervessel pits, rounded or angular and horizontal to vertical, of two distinct sizes or types in the same ray cell, 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.

Tracheids and fibres. Vascular or vasicentric tracheids sporadic to absent. Fibres very thin-walled. Fibre pits common in both radial and tangential walls, simple to minutely bordered. Helical thickenings absent. Fibres non-septate.

Axial parenchyma. Axial parenchyma present, not banded. Axial parenchyma apotracheal and paratracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma vasicentric. Axial parenchyma as strands. Average number of cells per axial parenchyma strand (3–)4. Unlignified parenchyma absent.

Rays. Rays present, multiseriate, also if only few, (1–)3–12(–22) cells wide, commonly 3–5 cells wide, commonly 5–10 cells wide, and commonly more than 10 cells wide. Rays with multiseriate portions as wide as uniseriate portions absent. Aggregate rays absent. Rays of two distinct sizes. 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 1 and 2–4. Sheath cells present. Tile cells absent. Perforated ray cells absent. Disjunctive ray parenchyma end walls indistinct or absent.

Storied structures. Storied structure present, some rays storied, some not, axial parenchyma storied, vessel elements storied, fibres storied. Arrangement of tiers regular (horizontal or straight). Number of ray tiers per axial millimetre 2.

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, upright and/or square ray cells not chambered. Number of crystals per cell or chamber one. Crystal containing cells of normal size. Cystoliths absent. Silica not observed.


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).

Index