Looks like stump sprouts from a Honeylocust that was cut down in the last year or so.

Well I'll be darned, very astute of you, I never even thought about that. I wonder if it's a honey locust cultivar because the leaflets on the native honey locusts around here (7a northern virginia) seem larger to me. But this definitely fits as a honey locust.

Could also be Mimosa (Albizia julibrissin) if it has really small leaflets. Looking at the new growth in the last photo, it does look like Albizia.

Doesn't look much like Albizzia to me.

I didn't think it was mimosa either; yeah the leaflets are bigger than that, not really small like you said mimosa would have. I'll get out of my car and check to see if there's a stump there which could help confirm honey locust.

Could be mimosa? The leaves look partially closed.Do locusts close their leaves at night? Anybody?

Doesn't quite look like the normal honey locust to me. Perhaps something else? But definitely looks like a resprout from roots.

Maybe it's not a tree.Could be a couple cassia marilandicas growing next to each other,but I'm not sure.

The plant is doubly pinnate so C marylandica wouldn't fit.

Thanks, I was more interested in getting people to consider it might be a shrub because I grow a few legume shrubs that get about that tall. I have no idea what it is at this point. I'm beginning to wonder maybe it's not a legume at all.

Since those leaves are evenly bipinnate and have acute tips, see if Leucaena leucocephala fits.

I really appreciate all the comments. So yesterday I went back and took more and better pictures. #1, it is definitely growing back from a tree that was cut down. #2, I took a picture comparing it with my mimosa seedling and it didn't look like it (see pic). #3, I think the leaflets are too small for honey locust.

I did look at Leucaena leucocephala but I get anywhere. It could be what it is, I did notice that the leaflets are opposite along the main leaf.

Here is a "big picture" of the whole plant, a picture of the sprouts on the left, stump on the right, and some better pictures of the leaves, with my hand and thumb for comparison. Hopefully this will help.

Here is a picture of the whole plant:

You can't see it very well because it's covered with tiny brown leaves, but the stump is on the right; you can see some of the black side of it in the bottom right of the picture.

foliage compared to a mimosa seedling:

leaflets compared to size of my thumb:

I was also thinking about what jaybirdyj said, about how it might be in the legume family. The leaves kind of reminded me of a pea cover crop I used a few years ago. So I looked up pea shrub, Caragana, and it might resemble that. But I'm interested in what you all think.

jaybirdy was saying it might not be in the Fabiaceae. But to me it looks pretty definitely in the pea family. Caragana is ruled out because this plant has doubly pinnate leaves.

I should have remembered they closed their leaves,so I'm leaning towards legume. I really like the ferny leaves and can't wait to find out what it is.

Yes, Jaybird's message just triggered the legume idea in my mind. Jaybird I did not realize they close their leaves. Yes I really like it too. Yesterday I was in the indoor greenhouse of a local garden shop and look what they had for sale, a bonsai pea shrub, Dichrostachys cinerea, looks a lot like it - I took pictures:

Two things:

1. the plant is clearly in the Fabiaceae.

2. it is apparently hardy where it is growing in z7. So it isn't Dichrostachys cinerea. (Note that is labelled 'Indoor')

The doubly pinnate leaves, the fact it is growing from a cut down tree trunk and the hardiness issue point to Gleditsia triacanthos, the first suggestion made.

Right, yes, I did know that it would not be hardy here, the plant being in the store's indoor greenhouse. I just thought the similarity in the leaves was more evidence of fabiaceae.

It does seem to be a honey locust but like I said in the beginning, it must be some intentionally planted cultivar, because the native honey locusts around here (and some of the street honey locusts too) have slightly bigger leaflets.

Thanks everyone!

The foliage of Honey Locust is quite variable even in the straight species.

Maybe it's a southwestern acacia species that was planted further north than its native range?