Could you give us a close-up of a couple of leaves? And maybe one showing the roots of an uprooted plant?

A close up

The root system and how the weed grows from the horizontal roots.

I think you have a member of the Ribes family - currants and gooseberries.It is an enormous family and contains both threatened and invasive plants. I hope that someone more knowledgeable than I will tell you what exactly you have growing there.

FWIW,my personal opinion is that anything that grows from underground runners is nothing but trouble.

Thanks - just from my short forays into pulling this weed it has been a nightmare. It's like a maze of roots. I pull up one root and it just keeps going finding more criss-crossing roots along the way.

Someone at work told me it might be a poplar? Any other thoughts?

I was hoping that someone would pipe up with a definite ID too, but,unfortunately, this is not the most active of the forums (ok, fora) here on GW. You could post this request with the pictures in the Name That Plant forum, which is full of plant wizards.

SOO I actually finally found out what this is. It is a tree. We have these trees in our yard that have massive underground runners spreading all over the place and according to the neighbors, they are impossible to control. I have no clue what type of tree it is but we think it might a species of gum tree.

The roots are incredibly destructive and invasive. We are planning on cutting them down as long as our next door doesn't mind. There may be an issue of who's property are these tree on. We are pretty sure they are on ours but not entirely.

Looks like elm suckers to me.