At this moment, American Black Walnut could very possibly be the most popular domestic hardwood. But did you know that American Black Walnut trees make up less than 1% of our US commercial forests? Add to that fact that the best walnut trees never make it to our sawmills. Asia loves American Black Walnut and pays top dollar for logs to cut into veneer. So unfortunately, we’re already at a disadvantage for getting the good stuff!
With such limited supply, hardwood manufacturers are struggling to keep up with demand. So, to make sure you get the best walnut for your money, it’s important to know your grades:
For all of the beauty of Black Walnut, as a tree it’s rather a mess, featuring many branches, twists, and contorted grain. Getting clear boards from walnut presents a challenge. So, since the beginning of lumber-grading history, it appears that walnut has been graded on a scale all its own—lower than… Every. Other. Wood.
The National Hardwood Lumber Association (NHLA), the organization responsible for managing grading rules, sets the following standards for hardwoods:
FAS Grade—First and Second (the highest, most well-known grade, and what you’ll typically find at your local hardwood retailer)
83.3% clear of defect on both faces
Overall board size: 6” x 8’
Clear cut area: 3” x 7’ or 4” x 5’
But for walnut, the FAS standard is lower.
Shrinks the allowable overall board size to 5” x 6’
Shortens clear-cut areas: 3” x 6’ or 4” x 3’
Allows splits up to 6” on one end and one defect
Allows two defects for boards 8” and wider
And the grades go down from here, to Select, #1 Common, #2 Common and lower. With each down grade, the clear material allowance drops and the usable board gets narrower and shorter. By #2 Common grade, the minimum clear-cutting allowance is only two inches!
Now let’s introduce Proprietary Grades: When you see retailers—Hardwood Lumber included—promote “Premium,” “Prime,” or “Superior” grades of walnut, there really is no such thing—at least as far as the NHLA is concerned. (Yeah, I actually asked!) The NHLA calls titles like these “proprietary,” which means that these terms and standards are defined by the seller (most often, the mill).
Next, I reached out to one of our vendors that supplies our black walnut, who directed me to hardwood manufacturer Missouri Walnut LLC. A leading walnut producer in the United States, Missouri Walnut states on their website that their Superior grade walnut has an “average 8” width and 95% clear cutting area, with excellent flatness, uniform color and grain.” These rules sort out boards that are actually better than FAS and therefore, command a premium price. We routinely stock above-grade black walnut, while always working to keep the price competitive.
Speaking of color, that light brown streak in your walnut board is probably steamed sapwood! You see, nearly all commercially harvested hardwoods are steam injected during the drying process to relieve stress in the board. But again, walnut is special…
Walnut sapwood is quite stark when compared to the natural chocolate brown of the heartwood and by grading standards, that’s a defect—so it lowers the wood’s value. Walnut producers have gone to great lengths to develop a steam process that darkens the young wood fibers. It doesn’t turn white sapwood the same dark color as the heartwood, but it does create a more homogenous scheme between the two. After the steam process, the sapwood is no longer considered a defect and allows the wood to be graded higher. (Ka-ching!)
As you can see, Black Walnut grades run the gamut and prices follow suit! Now armed with this information, you can feel confident in the material you purchase—no matter where you shop!