Plant ID southwest Oklahoma

Hello all, I am new here .I have been trying to ID this plant for 2 years. I believe it's a wild plum but it doesn't make any fruit. It has rooted itself to a cotton wood and is starting to spread across my yard like it's invasive. Thank you for any help

Hi Rebecca...and Welcome!  I'm in SE Arkansas and Prunus americana (or "Wild Plum") is typically found in the northern half of our respective states from what I understand. But you might have a good microclimate for it and it may have decided it liked your site. Plant ID is not my strong suit, sorry to say.  Have you snipped a sample (branch with leaves) to your local County Extension Agent to confirm your ID? Here are a couple of Wiki descriptions that might assist you: Wikipedia and Wiki's Practical Plants  

From your photo, it appears to be red osier dogwood (Cornus stolonifera) or perhaps one in the same genus.
They spread by underground stolons. We have them all over Michigan.
That is what popped up in my mind when I first glanced at the pic. Hope you solve your mystery!

The leaves alternate up the stem, so I believe the plum guess is better...something in the Rosaceae family, anyhow--dogwood leaves are opposite each other on the stem and not alternating.  Watch for five-petaled blossoms, probably white.  It would be interesting to see what it does over the course of the year.

It's not a dogwood unless it's the alternating dogwood but the leaves of the dogwood should have parallel vains.