Bouls Black Locust steamed 60 mm

The robinia tree originates from eastern North America. It owes its name to a French court gardener in Paris, Jean Robin, who brought the tree to France in the 17th century. The American name is "Black Locust", which translates as "black grasshopper". The species is so called because the dried legumes remain on the tree for a long time after the leaves have fallen and are strongly reminiscent of locusts.

For some years now, however, people have been reflecting on the outstanding qualities of the robinia, and there are now many approaches to increasingly consider the robinia in the afforestation of areas, with the declared aim of producing wood. All in all, with almost 2 million hectares (as of May 2001), Robinia ranks third worldwide among deciduous trees from plantations.

Trade names and other names

Abbreviation DIN EN 13556: ROPS
 Botanical name: Robinia pseudoacacia
 German: Akazie, Akazie natur, Akazie gedämpft, Robinie gedämpft, Falsche Akazie, Gemeiner Schotendorn
 English: Bastard Acacia, False Acacia, Black Locust
 French: Robinier, Faux Acacia
 Italian: Robinia, Cascia, Gaggia
 Spanish: Acacia de dos púas, Acacia de flor blanca, Acacia de los paseos, Acacia falsa, falsa Acacia, falso Aromo, Robinia
 Protuguese: Acácia bastarda, falsa Acácia
 Dutch: Robinia

Technical wood properties

Weight fresh/green: 800 - 950 kg/m³
Density air dry (12-15% u): 720 - 850 kg/m³
Tensile strength: 120 - 148 N/mm²
Compressive strength: 58 - 86 N/mm²
Flexural strength: 118 - 167 N/mm²
Shear strength: 16 - 20 N/mm²
Hardness according to Brinell BII: 67 - 88 N/mm²
Hardness according to Brinell B⊥: 25 - 43 N/mm²
Differential shrinkage (radial): 0.20 - 0.26%.
 Differential shrinkage (tangential): 0.32 - 0.38%.
 Natural durability (DIN-EN 350-2): 1-2, very durable to durable

Values of the technical properties of a wood species refer to a wood moisture content of u ≅12% to 15%. Data without guarantee.

Occurrence

The robinia originates from the east of the USA. Today the tree is naturalised practically worldwide. The robinia tree is often cultivated in plantations.

Trunk and bark

Robinia grows very quickly and up to 30 m high. The bark is thin and early forms a deep reticulated bark of a grey-brown colour.

Characteristics and wood colour

The sapwood of Robinia is rather narrow and yellowish, while the heartwood is greenish-yellow in colour. The wood colour darkens to a golden brown tone after a short time. Robinia wood is often steamed to a mocha-brown shade. the annual rings are clearly visible and delineated.

Replacement woods

Ash, hickory, white oak or tropical woods such as afzelia, bilinga, makoré, teak.

Literature
-Wood Atlas | 6th edition in 2006 | Rudi Wagenführ
-Wood science volume 1-3 | 1982 | Hans Heinrich Bosshard
-Properties and core sizes of wood species | 1989 | Jürgen Sell / Lignum Switzerland