This plant is growing in full shade on an eastern rocky slope. It is growing beneath various hardwood trees. If it is not Sarsaparilla what is it?
That was one of my first thoughts, but I don't recognize it. This area has an incredible diversity of hardwoods in a very small area. We just listed 16 different species of trees in sight of this plant. There is a Juglans nigra (black walnut) nearby which normally has more leaflets and a citrus scent when the leaves are crushed (this did not). Do walnut saplings have fewer leaflets than the full grown trees? This is the tree I suspect the most, but it does match imo. There are also a few different species of Carya (Hickory), but again not quite a match. I think the hickory leaflets are more opposite each other. No other trees in this area have leaves that look somewhat similar to this. The other trees either have leaves without teeth or are otherwise obviously not a match with lobes, etc. The tree is in 100% shade- I don't think the sun ever hits the ground in this area.
I saw a black walnut yesterday with some leaflets opposite and on other leaves, leaflets seemingly alternate. Here, for instance, is a photo showing white hickory leaflets partly opposite. Your leaflets seem more deeply serrated than what I'm seeing, except for maybe the Carya cordiformis on a Fox Island Alliance (Indiana) page.
Now I feel foolish - it probably is just a hickory sapling. The area is so shaded that a small tree probably will not survive long. We will have to check out the buds later to see if they are hickory buds. Thanks both for your help.
