I know they grow well in zone 5 in Ohio and survive below zero winter temps.

Rhonda

Probably zone 4/5 somewhere. It's much hardier than it's native range would suggest.

I can confirm they're all over Ohio (used to live there).

There is a mature one in a fairly open area at the Milwaukee Botanical Gardens. Thats zone 5b.

Based on its age it would have survived -25

Surprised to see Missouri Botantical giving it a zone 4 rating.

There are lots of N american natives that sit at 4/5, depending on source. Pawpaw, shagbark hickory, osage orange, persimmion..... Then they put the "hardy to -25 to -30C, which doesnt really help either.... Thats why i was asking because you do never know.

There are quite a few magnolias rated just the same. Stellata and virginiana for example. Then again there are tons of factors to think of when looking at tree hardiness anyways.

I've seen a large and stately specimen in central Illinois.

If you search this forum for "osage orange dublin ohio" you'll see an amazing one (not my pic) that is in a park that was 2 doors down from my house when I lived in Ohio. I took many family and senior pics on and around that tree :)