Black Locust (with Mineral Streaks)
Robinia pseudoacacia • Hardwood
Grain Pattern
Straight to slightly interlocked grain. This specific flat-sawn sample shows prominent growth ring patterns, cathedral peaks, and significant "ray fleck" on the face due to the large medullary rays characteristic of the species.
Color Description
Heartwood is typically yellowish-green to golden-brown. This sample shows notable dark brown to black mineral staining/streaks and bark pockets. It is highly lustrous and will darken to a russet brown with age and UV exposure.
Hardness Rating
1,700 lbf (Hard)
Durability Rating
Very Durable. Exceptional resistance to rot and decay; it is one of the most durable woods in North America, often used for fence posts and ground contact.
Common Uses
Outdoor furniture, decking, fence posts, boatbuilding, hardwood flooring, farm equipment, and firewood due to high BTU content.
Geographic Origin
Native to the Appalachian Mountains and Southeastern United States; widely naturalized throughout North America, Europe, and Asia.
Market Value & Sustainability
Estimated Market Value
$5.00 - $9.00 per board foot (varies significantly by region and grade).
Wood Age Estimate
Freshly milled or surfaced. The bright yellow/green hue indicates it hasn't seen significant UV's oxidation, which turns it brown. The tree itself appears to be of medium age based on the curvature of growth rings.
Sustainability Status
Not listed on CITES or IUCN Red List. Generally considered highly sustainable and often labeled as an invasive species in some regions, making its use ecologically beneficial.
Workability
Difficult due to high density and hardness. It has a dulling effect on cutting edges. Gluing can be tricky due to its dense nature, but it turns and finishes well.
Notable Features
Fluoresces strongly under UV (black) light, appearing yellow-green. Historically used for tree-nails in wooden shipbuilding because it is harder than white oak.
Finish Recommendations
Penetrating oils or film-forming finishes like polyurethane. If used outdoors, a UV-inhibiting clear coat is needed to maintain the yellow hue; otherwise, it will weather to a silver-grey.
Identification Confidence
High. The distinct yellowish-green color, prominent medullary rays (the horizontal hatch marks), and visible mineral streaks are textbook characteristics of Black Locust.