Robinia pseudoacacia L. (Robinie, black locust)
Nomenclature etc. PAPILIONACEAE. Trade and local names: Robinie, Falsche Akazie, Akazie, Gemeiner Schotendorn (D), robinier (F), false acacia (GB), black locust, yellow locust (USA), robinia (NL, I), ak t (CS), bagrem, robinija (YU), salcam (RO), akacja biala (PL), fehér akác (H).
Tree. Geographic distribution: Europe, excl. Mediterranean and North America.
General. Growth ring boundaries distinct. Heartwood basically brown to yellow to green. Sapwood colour distinct from heartwood colour. Basic specific gravity 0.54–0.74–0.87 g/cm³.
Vessels. Vessels present. Wood ring-porous. Vessels arranged in no specific pattern, in multiples, commonly short (2–3 vessels) radial rows and in clusters (both early and latewood). Vessel outline rounded. Average tangential vessel diameter 130–180–220 µm. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 7–11 µm, vestured and not vestured. Vessel-ray pits with reduced borders or apparently simple, rounded or angular. Helical thickenings present, only in narrow vessel elements, throughout the body of vessel elements. Tyloses in vessels present (extremely so), thinwalled.
Tracheids and fibres. Vascular or vasicentric tracheids commonly present. Fibres of medium wall thickness. Average fibre length 760–1000–1250 µm. Fibre pits common in both radial and tangential walls, simple to minutely bordered.
Axial parenchyma. Axial parenchyma banded. Axial parenchyma paratracheal. Paratracheal axial parenchyma scanty, vasicentric, and aliform. Aliform parenchyma lozenge. Axial parenchyma fusiform and as strands. Average number of cells per axial parenchyma strand 2–4.
Rays. Rays 6–8 per tangential mm, multiseriate, also if only few, (1–)2–6 cells wide. Rays of two distinct sizes. Height of large rays commonly 500 to 1000 µm, or commonly over 1000 µm. Rays composed of a single cell type. Homocellular ray cells procumbent.
Storied structures. Storied structure present (macroscopically hardly visible), axial parenchyma storied, vessel elements storied.
Mineral inclusions. Crystals present, prismatic, located in ray cells and axial parenchyma cells. Crystal-containing ray cells procumbent. Crystal-containing axial parenchyma cells chambered. Number of crystals per cell or chamber one. Silica not observed.
Miscellaneous. • Trees. Aufforstung mit Robinie in Nordostdeutschland - Black Locust afforestation in northeastern Germany - Aforestación con Robinia en el nordeste de Alemania. Robinia pseudoacacia. • Wood surface. Robinia pseudoacacia.
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).
