Commercial timbers

H. G. Richter and M. J. Dallwitz


Sorbus torminalis (L.) Crantz, Sorbus spp. (Elsbeere, service berry)

Nomenclature etc. ROSACEAE. Incl. Sorbus aria (L.) Crantz, S. aucuparia L., S. intermedia (Ehrh.) Pers. Trade and local names: S. aucuparia: Elsbeere. Arlsbeere (D); alisier, sorbier alisier (F); checker tree, wild service tree (GB); baccarello, ciavardello (I); aliso terminal, mostajo (ES); barkócafa (HU). S. aria: Mehlbeere (D); alisier blanc (F); whitebeam (GB); sorbo montano, farinaccio (I); serbal blanco (ES). S. aucuparia: Eberesche, Vogelbeere (D); sorbier des oiseleurs (F); rowan tree (GB); sorbo selvatico (I); serbal de cazadores, s. silvestre (ES). Status of protection under CITES regulations: nicht geschützt not protected.

Description based on: 4 species/specimens, or 15 species/specimens. Tree, or shrub. Geographic distribution: Europe, excl. Mediterranean, or Mediterranean incl. N. Africa and Middle East.

General. Growth ring boundaries distinct. Heartwood basically leicht rosa light pinkish brown. Sapwood colour similar to heartwood colour, or distinct from heartwood colour. Odour indistinct or absent. Basic specific gravity 0.65–0.75 g/cm³. Regelmäßiger Farbkern nur bei S. aucuparia, bei den anderen Arten gelegentlich Bildung eines dunklen Falschkerns only S. aucuparia develops regular heartwood, the other species only facultatively.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in no specific pattern, exclusively solitary or in multiples, commonly short (2–3 vessels) radial rows. Vessel outline rounded, or angular. Two distinct vessel diameter classes absent. Überwiegend solitär, in einzelnen Mustern auch mit größeren Anteilen von kleinen Gefäßgruppen predominantly solitary, ein some specimens also with larger protions of vessel groups. Average tangential vessel diameter 40–60 µm. Average tangential diameter of vessel lumina small. Average number of vessels/mm² 100–150. Vessels per square millimetre very numerous. Perforation plates simple. In sehr kleine Gefäßen kommen gelegentlich auch leiter- bis netzförmige Durchbrechungen vor (diagnostisch nicht relevant) perforations generaly simple; in very narrow vessels occasionally with scalariform to reticulate perforations (diagnostically not relevant). Intervessel pits opposite or alternate, average diameter (vertical) 5–7 µm, small, not vestured. Selten, wenig kompakt, gerundet rare, loosely arranged, circular. Vessel-ray pits with distinct borders, similar to intervessel pits. Helical thickenings present, in narrow and wide vessel elements, throughout the body of vessel elements. Tyloses in vessels absent. Other deposits in heartwood vessels present, rötlich braun, nur gelegentlich reddish brown, only occasionally.

Tracheids and fibres. Fibres of medium wall thickness. Average fibre length 800–1200(–1700) µm. Average fibre length medium. Fibre pits common in both radial and tangential walls, distinctly bordered. Helical thickenings absent. Fibres non-septate. Faseranteil zwischen 3714818nd 47(Wagenführ 1985) fibre proportion between 37and 47(Wagenführ 1985).

Axial parenchyma. Axial parenchyma present, banded or not banded. Axial parenchyma bands marginal (or seemingly marginal), fine, up to three cells wide. Marginale Bänder nur bei S. aucuparia beobachtet marginal bands observed only in S. aucuparia. Axial parenchyma apotracheal. Apotracheal axial parenchyma diffuse, or diffuse-in-aggregates. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 3–5.

Rays. Rays 8–13 per tangential mm, multiseriate, also if only few, 1–3 cells wide, 2–3 cells wide. Rays with multiseriate portions as wide as uniseriate portions absent. Aggregate rays absent. Rays of one size. Height of large rays up to 500 µm. Rays composed of a single cell type, or two or more cell types. Homocellular ray cells procumbent. Heterocellular rays square and upright cells restricted to marginal rows. Number of marginal rows of upright or square cells 1. Sheath cells absent. Tile cells absent. Perforated ray cells absent. Disjunctive ray parenchyma end walls indistinct or absent. Heterozellulare Holzstrahlen generell selten, am häufigsten in S. aria und S. torminalis heterocellular rays generally rare, most frequent in S. aria and S. torminalis.

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 not observed. Silica not observed.

Physical and chemical tests. Heartwood not fluorescent.


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).

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