Black Locust
Robinia pseudoacacia • Hardwood
Grain Pattern
Generally straight to slightly interlocked with a coarse, uneven texture. The end grain shows distinct ring-porous structure with large earlywood pores and wavy latewood bands (ulmiform pores).
Color Description
Heartwood is typically greenish-yellow to golden brown when fresh, darkening to a medium or dark russet-brown with age. Sapwood is narrow and pale yellow. It exhibits a high natural luster and is highly fluorescent under UV light.
Hardness Rating
1700 lbf (Hard)
Durability Rating
Very Durable. Renowned for its exceptional resistance to rot, termites, and moisture; often considered one of the most decay-resistant timbers in North America.
Common Uses
Fence posts, boatbuilding, exterior construction, deck furniture, mine timbers, railroad ties, and tool handles.
Geographic Origin
Native to the Appalachian Mountains and the Ozark Plateau in Eastern North America; widely naturalized throughout North America, Europe, and Asia.
Market Value & Sustainability
Estimated Market Value
$4.00 to $8.00 per board foot depending on region and drying condition.
Wood Age Estimate
The sample appears to be from a branch or small trunk approximately 15-20 years old based on visible growth rings and bark thickness.
Sustainability Status
Not listed in the CITES Appendices or on the IUCN Red List; considered highly sustainable and often an invasive pioneer species in some regions.
Workability
Can be difficult to work due to its high density and hardness. It has a high blunting effect on cutting edges. It turns, glues, and finishes well, though pre-boring is strictly necessary for screws.
Notable Features
Distinctive yellowish/greenish hue; highly fluorescent under blacklight; contains high concentrations of flavonoids and tannins which contribute to its extreme rot resistance.
Finish Recommendations
Teak oil or tung oil for exterior use to highlight the grain; film-forming finishes like polyurethane are suitable for interior use, though natural aging is often preferred.
Identification Confidence
High. The combination of yellowish heartwood, very thin sapwood, deeply furrowed bark visible on the edges, and the distinct ring-porous end-grain structure is characteristic of Robinia pseudoacacia.