Mimosa tree look-alike - What is it?

I have 3 seedlings that I thouhgt were mimosa trees and was looking forward for them to grow bigger and start blooming until I examined them closely and noticed they have tiny yellow single bean-like flowers on the undersides of branches. Little trees have leaves very similar if not identical to pink mimosa tree and liflets do fold at night time and when it gets very hot. I looked through a cople books I have and could not find exact match. Please, help me identify them. Thanks.

 

Please post a picture.

Regards
Chris

 

I'll do it tomorrow.

 

Meanwhile have a look at this.

http://www.alabamaplants.com/Yellowalt/Sesbania_herbacea_page.html

HTH
Chris

 

Flowers on mine are really tiny - no bigger than a leaflet. I am a work now and will take some pics when I come home tonight.

 

If blooming when dinky may not even be a woody plant.

 

It's definetly woody.

 

Here are pictures of my "mimosa". Flowers are bright yellow and did not come out well - a bit blurry, but it gives you a size reference.

 

Reminds me of Chamaecrista nictitans - wild sensitive plant.
http://www.easttennesseewildflowers...er-Roadsides-Yellow&id=Sensitive_pea_UTA20001

Newt

 

Thanks Newt. Mine are woody and perennial. They were growing at my work for a couple of years (one even longer) and I dug them up and took them home right before landscaping company was coming to spray for weeds.

 

Wish I could have been more helpful. Btw, I love your name. My kids have a Babusha on their father's side.

Newt

 

It means "old wonan" in Rassian

 

I've been told by my Russian in-laws it also means grandmother. That's what my kids call her.

Newt