Where are you located (approximately)? Obviously you recognize that you are dealing with a compound leaf. Hickory is an option. If you pull off a leaf/leaflet, is there a strong odor?

I'm in northwest ohio. What was interesting to me was that some of the "branches" have leaves directly across from each other while others are offset. There is zero smell if I pull a leaf; I even tore the leaf in half after that and crushed it. For what it's worth, the leaves are fuzzy.

Do you think the leaves are compound? I was thinking those were branches, giving me a simple-type leaf

This post was edited by tgtcat6 on Tue, Sep 10, 13 at 20:56

Not a hickory - butternut - J.cinerea; or, could be Japanese walnut, J.ailantifolia, its budsport the heartnut. J.ailantifolia var. cordiformis - or a hybrid of butternut with one of the J.ailantifolias.

DNA fingerprinting has revealed that a number of 'butternut' cultivars which are exhibiting resistance to butternut canker are actually hybrids.

Lucky, do these hybrids make Butternut nuts. In other words, would somebody like me be able to tell the nuts apart? (The average farm boy-type.) The reason I ask is because i would plant the hybrid. If I can get the nut without the threat of the canker, the purist in me goes out the window.

Yes that is a compound leaf. Come fall, that whole thing will separate and fall off, proving to all that it was a leaf after all. :)

I agree with Lucky butternut, heartnut, or hybrid of the two.

Thanks for the responses. So this is something I should let continue to grow instead of removing?

Is there enough room around it to reach mature size? This gets to be a good sized tree.

Yep, plenty of room. Wikipedia tells me it'll normally get 60-90 feet, which is no issue.