Black Locust — Robinia pseudoacacia
High, based on the deeply furrowed, fibrous, grayish-brown bark with characteristic orange-brown inner bark layers and the heavy, ring-porous log structure typical of Black Locust. confidence

Black Locust

Robinia pseudoacacia · Hardwood

Type
Hardwood
Origin
Native to eastern North America, but widely naturalized throughout North America, Europe, and Asia.
Hardness
1,700 lbf (Very Hard)
Durability
Very Durable (exceptional resistance to decay and rot, highly durable against insect attack)

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Grain Pattern

Straight to irregular grain with a coarse, uneven texture and distinct ring-porous structure.

Color & Appearance

Heartwood is a golden-yellow to greenish-brown, which tends to darken to a deeper brown upon exposure to light. Sapwood is a contrasting pale yellowish-white.

Hardness (Janka)

1,700 lbf (Very Hard)

Durability & Decay Resistance

Very Durable (exceptional resistance to decay and rot, highly durable against insect attack)

Value & Sustainability

Estimated Market Value
3.00 to 6.00 USD per board foot for rough-sawn lumber.
Wood Age Estimate
Freshly cut log, estimated tree age before felling was approximately 40 to 60 years based on ring spacing and log diameter.
Sustainability Status
Not listed on CITES appendices and not considered threatened by the IUCN. Highly sustainable and abundant in many regions.

Common Uses

Fence posts, decking, shipbuilding, exterior furniture, turnings, and mallets.

Geographic Origin

Native to eastern North America, but widely naturalized throughout North America, Europe, and Asia.

Workability

Very difficult to work with hand and machine tools due to its extreme hardness and density. It tends to blunt cutting edges quickly, but glues and finishes reasonably well.

Finish Recommendations

Penetrating oils or exterior-grade finishes work well. Polyurethane can be used for interior applications, though surface preparation may require thorough degreasing if natural oils are present.

Notable Features

High shock resistance, exceptionally rot-resistant without chemical treatment, heavy weight, and contains toxic compounds in the bark and leaves.

Learn more about Black Locust in the Wood Encyclopedia
Identified August 15, 2026