Appears to be suckers rather than seedlings. Could be Malus suckers. Is there an apple tree nearby or one which has been cut down?

Agreed, definately a Bromeliad which is a tropical (family of Pineapple). Perhaps do an image search re: Bromeliad & see what photos might match your plant. Maybe an Achmea, but I don't recall them having spines on their edges.

I agree litterbuggy. It really is a cool looking plant. I've never seen one like it.

Viola sororia can spread around, but removing it is so simple that I find it amusing how some people love to discuss it's 'weediness' again and again and again, like a broken record ==>> my premise was the definition of a weed ... which includes:: -anything you dont want in your garden -anything that pisses you off.. e.g. it seeds around a lot -etc.. etc.. etc ... so basically.. you accept my premise it seeds around . and then you tell me my opinion is wrong ... nice circle there ... its all about what the OP .. original poster wants to define weed as.. make her own opinion.. based on the observations of her friends here ... i am debating jay.. not arguing ... dont read anything further between the words ... ken ps: native or not really has no impact on whether a plant has value to you.. in your garden.. under your definition of what is a weed ... in other words.. there are a lot of native weeds .. that might not belong in your concept of what your garden is ...