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Nomenclature etc. FABACEAE-FABOIDEAE. Trade and local names: Robinie, Falsche Akazie, Akazie, Gemeiner Schotendorn (DE), robinier (FR), false acacia (GB), black locust, yellow locust (US), robinia (NL, IT), akat (CZ), bagrem, robinija (CS), salcam (RO), akacja biala (PL), fehér akác (HU). Not protected under CITES regulations.
Tree. Geographic distribution: Europe, excl. Mediterranean (naturalized), North America.
General. Growth ring boundaries distinct. Heartwood basically brown to yellow to green. Sapwood colour distinct from heartwood colour. Density 0.54–0.74–0.87 g/cm³.
Vessels. Vessels present. Wood ring porous. Ring of earlywood vessels multiseriate. Vessels arranged in no specific pattern, in multiples, commonly in short (2–3 vessels) radial rows and in clusters (in 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, pits 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 present (extremely so), thinwalled.
Tracheids and fibres. Vascular or vasicentric tracheids commonly present. Fibres of medium wall thickness to very thick-walled. 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 (bands may partially include earlywood vessels). Bands marginal (or seemingly marginal). Bands coarse. Axial parenchyma apotracheal, or paratracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma scanty, vasicentric, and aliform. Aliform parenchyma of the lozenge type. Axial parenchyma fusiform and as strands. Average number of cells per strand: 2–4.
Rays. Rays 6–8 per tangential mm, multiseriate, (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); 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.
Physical and chemical tests. Heartwood fluorescent (bright yellow).
Illustrations. • Trees. solitary Black Locust tree at the Royal Botanic Gardens, Kew, England. • Macroscopic images. transverse (ca. 10x). tangential (natural size). • Transverse section. • Tangential section. axial parenchyma cells (AP) storied. AP. • Radial section. • Tyloses; spiral thickenings. complete blockage of vessels by tyloses. spiral thickenings in latewood vessels. • Crystals. prismatic crystals in ray (left) and axial parenchyma (right) cells, generally infrequent.
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: 9th April 2019. delta-intkey.com’.
