maybe a black walnut w/o the green husk? just a guess. I only vaguely recall them looking this way.

It doesn't look like black walnut to me -- wrong shape and too small. I'm a couple hours south of OP and I've never seen anything like it. It's difficult to tell from the photo -- is it a hard outer shell? Where did you find it? Have you tried breaking one open?

How big is it? If it was large (greater that about 2') enough it could be an osage orange. https://en.wikipedia.org/wiki/Maclura_pomifera

When the "oranges" fall off, and turn brown the could appear to be the "nut" you have

Theres a ruler in the picture if you click on it. They’re about 3/4 ” diameter.

Can you cut one open? What’s inside?

My swamp white oak gets brown, woody galls (or some kind of abnormal growth) on the end of stems that look alot like that.

Actually agree it looks like an oak gall.

I was thinking it was an oak gall after I thought about it. It was found beneath an Oak. I didn't find it but was asked if I could help ID it.

Split it open. Looks like larva in it to me. Like a gall, no?

Might be the oak bullet gall shown here.,.

http://hyg.ipm.illinois.edu/article.php?id=778

tj

I always forget the the picture you see in the message is not the picture you get when you click on it

Same thing happened to me krnuttle!

What do you mean about the pic not being the same when clicked on?

It enlarges when clicked to show more.

tj

Right, that's what I thought. I guess I thought krnuttle meant something else...like something was happening with the pictures.

I think tsugajunkie's link looks pretty close.