I don't know what it is. It looks like some kind of chrysanthemum, doesn't it? I've seen it get 4 feet high and not even bud. Whatever it is...I'd get rid of it. It's very, very aggressive.

Thank you for replying! You are so right, it is very aggressive! I found it in our yard several years ago, and it just pops up everywhere. I've pulled them out by the handfuls, but they keep coming back in scores! I have one that is about 3 feet tall, now. I think I'll let that one go through whatever it's cycle is, and see if it does anything.

Compare with Artemisia vulgaris.

Personally, here's what I did, because I hand pulled and dug for YEARS and it still didn't do anything to this whatever it is. Didn't make a dent. I used Round-Up. Sure fixed the problem fast. Haven't seen it here for a long time.

"Compare with Artemisia vulgaris."

I almost thought that might have been it, when I saw your post and first looked it up. But, when I looked at more pics, it seems that the leaves on the one I have are wider, and the one's on the Art.Vul. are thinner.

"I used Round-Up. Sure fixed the problem fast. Haven't seen it here for a long time."

That's a thought. I don't like to use round-up, unless I have to, because I don't like to use chemicals near my gardens. The only time I've resorted to it, was for poison ivy :O LOL.

I have one I'm letting grow, and I'm going to let it grow. Hopefully, it'll start to show some sort of other characteristics that will help to identify it :)

I don't like to use chemicals in my gardens either...but sometimes, every once in a great while...I have to. The stuff you have is a great occasion to use it...just paint it on the leaves with a paint brush.

I have a big heath-aster problem here. Yes, it's native. Yes, it will take over an entire garden if you don't nip it. So, I did. A combo of round-up and cutting. There aren't enough hours in my day to hand pull all the nasties that come up, though I prefer hand pulling. April