Alium canadense; Liliaceae

You know that common weed that makes your yard smell oniony after you’ve cut the grass?  If you can stand it, try letting some grow.  It’s a pretty flower:

and purportedly edible.

However if you see this one, pull it out fast:

That’s field garlic, Alium vineale, an invasive alien. Although not poisonous, it has an unpleasant taste.