Thank you, susan. This means what I have COULD be allium., but since it could also be onion grass, how does one tell the difference?

Do you know what species of Allium you had? And do you know what species the 'onion grass' is? Some Alliums have cylindrical leaves and some flat.

Here in the Hudson Valley it's my experience that the onion "grass" grows in really thick, tight clumps in places you don't want them, and the good alliums are more separate in growth, altho together in one place. After you've gotten used to them, you'll get to know the difference.

For a few years, keep a diagram of everything you plant. That'll help a lot.

Floral, I had to check my records... They were allium sphaerocephalon - pink drumstick allium. Prolific in several locations the first year, then disappeared, so it appears I'm looking at a double failure - to spread or to reseed. I did not cut them back too early as I recall suffering through a long period of unsightly stems flopping into the path. Voles? I would appreciate knowing if the leaves are cylindrical or flat.

Suzanne - Your distinction is helpful. Could we also say that an onion grass clump includes very fine and short stems (is that the right word in the case of a grass?) while allium leaves are more consistent in size?

A. spaerocephalon has cylindrical leaves so I'm afraid you wouldn't really be able to tell them apart from A. vineale, if that is the species you mean by Onion Grass, until they flower.

I'll send you some pictures of the two after this foot of snow melts. My advice is to let them all grow and then decide what to dig up when you see the flowers. (Don't let them go to seed.) The weedy stuff is very tightly together and clumps are easy to dig or pull if the ground is soft. Don't sweat it right now. Enjoy this snow!