While Grant Stone tends to skew towards a dress-casual aesthetic in its patterns, that hasn’t stopped them from embracing more rugged or exotic leathers. Kangaroo, kudu, ostrich…they’re not afraid to be adventurous.

The latest addition to Grant Stone’s stable of unconventional leathers is American bison, which can now be found on their Diesel Boot. Built on the Leo last, this Diesel Boot features Walnut Bison from Milwaukee tannery Seidel. This burly leather is complemented by brass hooks and eyelets, a 360 storm welt, and Grant Stone’s commando soles. You can pick up a pair of your own for $370.

grant stone diesel boot walnut bison

It’s worth noting that American bison is often colloquially referred to as “buffalo,” but the buffalo of Africa and Asia are a different bovine species from the bison. Bison are distinguishable from buffalo for their large humps and relatively small horns. 

American bison are actually the national mammal of the United States, and at one point there were an estimated 60 million bison on the North American continent. Unfortunately, the bison was hunted to near extinction, but thanks to conservation efforts its population today is on the path to recovery.

grant stone diesel boot walnut bison

Since bison is part of the bovine family, you can provide it with more or less the same cleaning and conditioning regimen as you do on other cowhide leathers. The chief differences here are not just with the leather’s appearance, but also its strength. Bison leather has roughly 40 percent more tensile strength than a comparable cowhide leather.

I asked Giovanni Doveri, customer service and media manager at Grant Stone, what his impressions were like of these Diesel boots compared to some of GS’s other leathers. To him, the leather is almost like a cross between a cow and a kudu. “A cowdu, if you will.”

While kudu is relatively more uniform in appearance with its ample scarring, Doveri said you can expect to see a lot of variation in bison leather’s pebbled texture along with its creasing. He provided us with photos of two different pairs to illustrate this point.

grant stone diesel boot walnut bison

grant stone diesel boot walnut bison

Doveri also noted that there’s a much more waxy hand to this Seidel bison leather than you might find on something like C.F. Stead’s Waxy Kudu, which you can find on a couple other Grant Stone models. He described this leather’s waxiness as being somewhat akin to Horween Chromepak. 

Overall, Doveri summed up the leather as “unique in the best sense of the word.” It certainly is!

The Diesel Boot in Walnut Bison