What is this plant?

I'm in eastern Ohio and I am curious about this plant that I have growing on my property.
I'm worried about the possibility of poison sumac as I have a toddler running around and I know it's just a mater of time before he gets into that area! Thanks in advance!

Black walnut seedling.  The seedlings have fewer leaf pairs than are found on the adult plant.

Thank you Mike! I have a couple more pictures of things I'm wondering about as well. If you could help that would be great! As you can tell, I don't have much knowledge about anything regarding plants!

Couple more.

The first pic is a hickory tree. Might be a Mockernut, hard to tell when they are that small. Second pic is a white ash. Next you have a few pictures of Ailanthus altissimo, or tree of heaven, scrape the bark and it will smell like rancid peanut butter. Very bad tree, kill by any means necessary. More importantly you need to find the adult female tree and kill it, sets a ton of seed. Last pics, the vine, is Virginia creeper.

You guys are amazing! Thank you so much!

This one is the only thing that concerns me, being that it is the typical 3 leaves like poison ivy does. It's under my deck and that part is open and easily could be touched by anyone. If it had more than 3 leaves then I would feel better about it, but that's what keeps me concerned. If I need to pull it up I will gladly do that. I've read a lot about poison ivy and how the middle stem is bigger than the sides and obviously that is the case here as well. If you could let me know what makes you think it is something other than that, that I'm just unaware of that would be great!

I must admit I thought walnut too but we have Persian ones here in Europe

That is definitely not poison ivy. It does have the 3 leaves like you said. On poison ivy the center leaf will have a tooth or lobe on either side of the leaf. The 2 leaves on the sides will have a smooth inner edge and on the outer edge it will have a tooth or lobe. Pretty easy mistake to make since the ash does have a somewhat glossy/shiny leaf.

That 3 leaved plant is an ash seedling.  Poison ivy isn't opposite leaved and has lobed leaves.

Thanks again! And you are sure this is not sumac? I am just a little over paranoid being a 1st time mom with a toddler running around!

The vine climbing out from under the concrete blocks in one of those photos above is Virginia Creeper. A few people get a poison-ivy-like reaction if they pull and break virginia creeper and get the sap on their skin. I've pulled a lot of the stuff and get no reaction at all. Its tiny little seedlings or sprouts often have only 3 leaves and look like poison ivy. Virginia creeper is one of those invasive tree-killing vines that climbs up trees looking for light and smothers the canopy of the tree. In New York state I've seen whole patches of woods taken down by Virginia creeper so that they look like some weird green glommed alien victim or something.

I've pulled a lot of invasive vines in Massachusetts. There's no poison ivy right on the property but is lots in the neighborhood, so I try to always take precautions after weed pulling, and wash my arms, feet, and any exposed skin with soap right after a vine-pulling session. If you've touched poison ivy but wash with soap before the oil has a chance to get into your skin, then you won't get the rash. I'm very reactive to poison ivy but this works for me, even when I know I've been heavily exposed.

I just checked my Audubon tree guide, and the description for poison sumac reads (italics theirs): "Leaves: pinnately compound; 7-12" long; with reddish axis.  5- 13 leaflets 2 1/2- 3 1/2" long; paired except at end; ovate or elliptical, without teeth; short stalked.  Shiny dark green above, paler and slightly hairy beneath; turning scarlet or or orange in early autumn."

Based on that, and depending on where in the country you are, I'd rule out poison sumac; the leaves in your picture are definitely toothed.  As for what it *is*, I wouldn't feel comfortable trying to identify it myself because I'm no expert.

edited to add: The Audubon guides are a really great resource, imo, and are well worth the price for the hard copy (I just looked it up and they have apps and digital versions, too).  My family's copies are 30+ years old and we still use them at least a few times a year (mostly birds, but also trees).

Hey guy's,

We are in Seville Ohio hr south Cleveland and 30min west of Akron.  Please help me identifying some more Ohio Plants!

A few more thanks for any help!!!

The first picture I thought could be eyesight.
The last picture I thought bungle?

Last purple one looks like Heal All.

This is actually Butternut tree (Juglans cinerea),