What onion is this?

Came up this spring on its own.

looks like a regular ol' green onion

what was the last thing you had planted there I would guess yellow looking at the paper

every year some onions get missed loose their tops in the weeds or whatever and they sprout back up as soon as it gets to some warm days and the Siberian Squill blooms.
if you didn't till in the fall

because it is a 2nd maybe even 3rd season onion it will probably make a seed head quick so using them as green onions of early spring works for use.

garden salad onion i think

WA Vinke toed onion.

This is a place my niece just bought over the winter and these came up. They're watching for asparagus too!

Looks like my
Egyptian Walking Onions
A multiplying variety.
They are perennial.
I cultivate mine for the Scapes.
One of the first green in the spring.
I usually cut them to harvest as needed.
Not sure why , just the way my mom did it,

Walking Onions

Walking onion is one name. My dad called them winter onions. They live over the winter and come up in the spring. Will have small bulbs on the end of stock in the summer. Are good in the spring and fall. Hot in the summer.

Have a friend down here that thought he was getting wild onions

Turned out to be something called "crow poison" and he said for a couple of days he wished he would die so he could get some relief.

Broke me from eating anything I don't know with certainty what it is