Lilium lancifolium. aka tiger lily.

illustration on left below:

http://www.efloras.org/object_page.aspx?object_id=7360&flora_id=1

Thank you! I am guessing they are somewhat invasive?

Is there a way of knowing this is lancifolium and not another lily?

There are not a whole lot of lilies with stem bulbils that produce weedy colonies. And this one is particularly weedy. In Pennsylvania and surrounding states. I dug up hundreds of them . I won't grow it here in NC.

OP states it is growing in New Jersey and popping up everywhere. I know of no other lily that is that prolific.

http://www.efloras.org/object_page.aspx?object_id=8364&flora_id=1

https://www.minnesotawildflowers.info/flower/tiger-lily

The plant looks much more like Asiatic lily.

It does look like an Asiatic but I agree with what Carol said. Asiatics don’t pop up everywhere.

tj

It looks like, tsugajunkie, you have never seen those that do.

I agree with carol that there are not a whole lot of lilies with above the ground stem bulbils. Asiatic don't produce them either. They, at least some varieties, multiply by producing offsets under ground

Like this https://bdlilies.blogspot.com/2014/06/be-mindful-of-lily-bulblets.html

I see no bulbils in the picture of the lily asked about. Also I am not sure those are tiger lily leaves. If it were my situation I would wait for confirming flowers before undertaking removal.

Could it be Horseweed (Conyza canadensis) ?

It is unmistakably a lily. Looks most like one of the Asiatic hybrids but you won't know for sure until it flowers.

"not a whole lot of lilies with above the ground stem bulbils. Asiatic don't produce them either."

Windberry, you should have reviewed your source link a bit closer. Asiatic hybrids can produce bulbils, although not all do: "Bulbils can be found quite readily on the old fashioned Tiger Lily (L. Lancifolium) and other Asiatic Hybrids that, in their breeding background, have that tendency".

Yeh, I've been looking for these bulbils too. Still can't see any. If DD is new to this garden the 'popping up everywhere' could simply mean that lilies were planted in quantity by the previous owner. Seeing the flowers will settle it.

And no, it isn't Horseweed.

Yes: a lot of people think if they have multiples of a plant they are being overrun, it is an invasive weed and so on.

Difficult to see what is under ground indeed. I have Asiatic Lilies in my garden for about 20 years and have never seen bulbils on the stems either. As with many other plants I started with one bulb only. Over the years the clump was getting bigger and bigger. Two years ago I got voles in my garden and now I have Lilies in many other places as well. I am pretty sure that OP's DD garden is (or was) vole infested. Hopefully he will post pictures of the flowers soon.

I will tell her to send me a picture when it flowers so we can have a big reveal.

Bulbils are not formed this early in the season. It is not until the flowering stems are fully elongated and it is close (if not past) to bloom time that they become apparent.

Lilies can also spread by having the stem bulblets or the offsets moved or disturbed. This is easily done by the gardener just cultivating in the area and not realizing they are moving around tiny little baby bulbs. And as noted, the bulbs and bulblets are also easily displaced by critters.

Any follow up on these? I have the same pop up and it's 'killing me' not knowing what type it is. I have 0 patience 😂

I have the same problem. It just popped up in a pot stored in my garage.

Lillies all look pretty similar before they start to flower. Unless you post a picture of your actual plant, anyone who answers is just guessing. btw a lily appearing in a pot would not be 'problem' in my book.

Did the plant ever bloom? We were promised a photo!