What tree is this?

NW Arkansas.

Butternut?

Butternut has a smooth oval to egg shaped hull that looks like a black walnut since it is a walnut.
Hickories ave a four part shuck.

Looks like a Bitternut Hickory, AKA Swamp Hickory

hickory

Bitternut

Called pignut hickory in PA.

Best variety of hickory wood for the smoker.

I cut a dead one of those down and cut into firewood length and delivered it to a buddy for fire wood. He was not able to split it with a Monster mall.
Hard as woodpecker lips.
I did the same to another one once and most of the rounds rolled down towards the water's edge. I figured, no problem, I'll fish them out once I was done cutting the rounds up. I got finished and there was not one round to be found. They are now in the bottom of that lake. It don't float!

High octane wood for extra cold nights.

Scallybark hickory...
Squirrels favorite...
Well, maybe...how big are the nuts?
Just seen the bark

Pignut

The trick to split hickory by hand is to first split narrow slabs off of the sides. It seems once you get the outer couple of inches off, the rest of it splits normal.

I'd say its a pignut hickory too.

Thanks guys. I'll try it on sow belly!

Buckeye...

pignut

The trick to split hickory by hand is to first split narrow slabs off of the sides. It seems once you get the outer couple of inches off, the rest of it splits normal.[/quote]
What you say is generally true in my experience, but when they die standing, something happens to the wood which makes it much harder to split.

Black Walnut

I can see why you would assume that. I did at first until i zoomed in on the nut which looks like it had resided near the hind end of a pig.

To add some diversity to my property I'm considering maybe planting a few bitter nut or shag bark Hickory