Please help ID this large leafed plant with tuber like roots!

I have a bunch of this stuff growing in the corner of my property. It dies back in the winter and comes up every year. It has large tuber like roots and I keep cutting it back and it keeps growing back very quickly. It seems to get 4 feet or so wide and about the same tall. but probably could get bigger if I wasn't cutting it back. I bought this home last year and noticed it growing out back where the previous owner seemed to pile all their leaves.

It reminds me of four o'clocks (Mirabilis jalapa), but the leaves look somewhat different. Maybe a different species of mirabilis? They definitely have tuber-like roots.

This looks like a datura, or jimson weed. Very poisonous to anthing that eats it. Looks like a wild variety.

Does the seed pod have thorns?