Acquired 2 of these, I want to say they are mesquite trees but I honestly know nothing about trees. Are there different kinds of mesquite? Do we know what this looks like?

If they are mesquite, I see these in the neighborhood and they are HUGE and home owners pay landscapers at least once a year to come hack down a ton of the tree. Seems like they grow at a very very fast rate.

Do they have a lot of droppings? Not a fan of the tree making a mess of my yard.

If I were to plant these in a pretty large planter instead of the ground, will they stay a manageable size since the roots can only grow so much?

Thanks for any insight!

I don't think its a Mesquit but I'm not sure what it is.

Could it be Cassia?

I agree that it doesn't look like mesquite - more like mimosa, perhaps.

Could it be palo verde? They are very very popular around here but have green trunks it seems.

Most pics of "mimosa" tree show more pointed leaflets, but otherwise, that's what it looks like to me. It's a shame that nobody, including me, has put more pics of the bark in the plant database. It's distinctive.

Pics to compare.

mimosa tree:
Mimosa Tree (Albizia julibrissin)

Entries for Cassia:
https://garden.org/plants/sear...

purpleinopp said: Most pics of "mimosa" tree show more pointed leaflets, but otherwise, that's what it looks like to me. It's a shame that nobody, including me, has put more pics of the bark in the plant database. It's distinctive.

Pics to compare.

mimosa tree:
Mimosa Tree (Albizia julibrissin)

Entries for Cassia:
https://garden.org/plants/sear...

I just posted a pic of the trunk of one of the mimosas growing here!

Very nice. Thank you, Kathy!

Since I originally posted this 3 months ago, they dropped ALL leaves and most small branches. I kept watering and now it's getting hot (Arizona) so they're coming back strong! I still have no idea what these are! Maybe some updated pics with fresh leaves will help?

I went back to the house where we obtained these trees and found that they have a more mature one. Maybe this helps identify seeing a more mature trunk? Unfortunately, the home owner has passed so I can't ask what they are or where they got them.

The pics show pairs of opposite leaflets but are the actual leaves opposite or alternate?

They look alternate to me - with much guessing.

This would be opposite, right?

Could it be a tamarind tree?

Yes. Those are leaflets. Can you show how the whole leaves come off the stem?

From everything I see in all the images presented - none of which have focused on one whole leaf - I think this plant has bipinnately compound leaves.

Since I'm not from the great southwest - though I have enthusiastically visited there over the past dozen year or so - I'm not going to be a great help in IDing this species, but I can give diagnostic coaching. I don't think Cassia is bipinnate (could be wrong), and I wouldn't know a Tamarind if it caught me in a dark alley. Albizia julibrissin IS bipinnately compound.

It's NOT Aralia or Gymnocladus sp....

The original photos were posted in January. Did they have leaves in January?

porkpal said: Yes. Those are leaflets. Can you show how the whole leaves come off the stem?

I'm sorry I don't understand what you mean by this. Happy to take additional pics, though!
Are you asking for a pic that shows a stem without leaves?

DaisyI said: The original photos were posted in January. Did they have leaves in January?

The pics posted in January were taken at the same time, yes. I transferred the trees to my house then, they started losing leaves/stems almost immediately. Almost as if they were mad at the transfer, but they're coming back very strong right now (April in AZ)!

Mkw, your tree has compound leaves consisting of leaflets (each little green bit) connected to the overall/entire leaf. Your pics shows leaflets that are opposite, and midribs that are opposite, but a pic showing whether the entire leaves (including the rachis) are alternate or opposite can help with ID by eliminating some suggestions, and supporting others. This site has a good introduction to the terms, lots of pics:
https://www.treehugger.com/sim...
I have no connection to the linked site, having never clicked on it before today, can not vouch for the intentions of its creators or owners. It came up in a search and had few enough ads that it loaded in a reasonable amount of time and the pics convey visual information I think would be helpful to this discussion.