Wish I knew, too, and I hope someone has the answer. I had a very large stand and at first thought they were Rudbeckia, but the leaf didn't look right. I finally pulled mine except for three that I transplanted with some Ruds. Definitely not the same leaf but I'm letting the three grow until I know whether it's friend or foe.

Barbara in Virginia

Every time I pull them its probably a plant, anytime I leave them its a weed..

See wasnt that helpful!

But really , I had like a billion reseeded plants, and I pulled them, turned out the couple I left it was annual Silene, wouldve been nice to leave them, oh well..

At the stage its at, you might just want to leave for a week or two more, if its a weed, just yank it before it seeds.

Silverkelt

I have pulled "weeds" only to find that I had previously carefully amended the holes they were planted in. Our heavy clay soil and garden budget doesn't allow for the whole large bed to be "fixed". So,the plant goes back in and fingers are crossed.

your photo looks very like the Giant Ragweed pic in my weeds of the northeast book... are the leaves opposite or alternate? opposite = giant ragweed (Ambrosia trifida). not certain of your plant, just a possibility. if it is, then get rid of it, as it's the hay-fever culprit. =)

I think it looks like black-eyed susan. I'm attaching a picture of some of mine for comparison.

I pretty sure roxanna is right. I tried finding an image of a weed very much like in thinman's photo, in my old weed guide but couldn't. Then I Googled "Giant Ragweed" as posted by roxanna. Pretty sure that's the weed that grows in abundance here along field edges and brushy areas, most every where. The bloom comes right from the center of the cluster of leaves and starts out in a cone shape. I thought they were yellow if my memory serves me, but in the Google images I can't tell. Mature plants are tall.

I pulled the three that were in my front bed. Also wondered if they were ones I moved there last fall but my friend assured me they were weeds and they only grew taller the next week so decided she was right and pulled.

It also looks like it could be a chenopodium

Here is a link that might be useful: chenopodium

Mystery solved. Cbusgirl, you nailed it. I remember now that it is a rudbeckia triloba. I started some from seed last year but I couldn't remember where I had put the few I had left, or even if I did put them in for sure. As soon as I saw the photo and the words black-eyed susan, it came back to me.

If only I had read this yesterday before I pulled them. Yes, indeed, I did. Aaaargh! The second I pulled them up, I saw little pieces of perlite among the roots and knew that I must have started them, though I still couldn't remember what the heck they were. Barbara gave me a good hint with her comment about the giant ragweed looking like rudbeckia, but it didn't click with me then.

Thank you all for helping me with this. It may have not had a happy ending, but it's still good to know for sure what it was. Dang, though, I would have really liked to see those blooming.

ThinMan

Shoot ... then I pulled up a thick stand of my favorite Rud ... boy, they were healthy looking ... why, oh why, can't I remember what weeds look like from year to year, especially the ones that resemble "legitimate" plants ... at least I didn't pull the three I rescued and transplanted elsewhere as a test ... thinman, I'm so glad you posted the question and thanks for all the responses

Barbara in Virginia

Oops. Guess it wasn't ragweed then. :(

Guess not, Schoolhouse. Still, it was pretty darn close.

Sorry you pulled yours too, Barbara. When will we learn?

TM

I pulled up SO much of this the first year we lived in our current house. It looked like a weed to me, too, especially because it pops up everywhere! Now, I still pull most of it but leave a few patches.

I dont' always take time to label and the metal labels are hard to write on and the sharpie plastic labels fade, so sometimes I just stick a blank label in the ground or a popsicle stick just so I know this is not a weed, and even though I don't know WHAT it is, I know it is something I planted!
Laurie

Well, now I'm not so sure it's Rudbeckia. I was cleaning up a bed this morning in preparation for spreading mulch, and the same plant was there, next to giant blue hyssop, which I planted in that bed two years ago. The leaves look identical when I saw them growing side by side. I also had hyssop near the other bed where I pulled up the "weeds." So now I'm thinking that plant is hyssop. I still have the three I transplanted elsewhere, and if and when it blooms, I'll know for sure.

Thinman, did you have hyssop near the "weeds" you pulled?

I have another plant that just showed up elsewhere. I don't remember planting it. I left it because it just looked so intentionally placed. It has large, heart-shaped leaves. The buds look like hibiscus but it shoots up a stalk about 8 inches tall with pale lavender blooms all along the stalk. It has a lot more buds forming.

Gardening sure holds surprises.

Barbara in Virginia