There are many species of Epilobium, some of which have had name changes, like the fireweed. Some are native, some are introduced weeds. There's only one fireweed though, by whatever name. Watson's willowherb is a common garden weed, I think it's Epilobium ciliatum now, used to be Epilobium watsonii. Dry or damp, sun or shade, tall and rank or short and sparse. Seeds, no runners. The one in your garden is probably the Watson's although you may also have others like Epilobium minutum in dry spots. I'm sure bboy is much more knowledgeable about the various species than I am, I usually do well enough just going by 'Epilobium species'. What you have in the photos on the Weeds forum sure look like Watson's willowherb gone to seed. They've done really well this year with the cool damp spring. But the photos do need to be larger to really see. I'm just guessing from the silhouette.

Hard to tell from the picture, but check out Houttynia cordata. Looks similar, but I may be wrong. If my guess is correct allow it to grow, use herbicide - then allow it to re-grow, use herbicide - keep repeating. A plant that should not be allowed. hortster

Red, after you cut it off the next time, can you pour boiling water on it? I might stick a long screwdriver or other similar object in the ground right around it before doing so also, to help it penetrate around the root while still hot enough to be lethal. Will make a dead spot in the grass, but that's easy to fix, much easier than trying to dig something out of a fence. Killing something by the method you describe requires doing it often, daily for some things, and can take a long time. You have to remove any growth faster than it can be reproduced, so the roots eventually run out of stored energy. Anything large and woody enough to move CL fence is not going to die from occasional beheading. I share your frustration. I thought I'd killed a Mimosa stump *in* our CL fence and then planted a rose in front of it. Then the stump kept growing, so I can't pour boiling water or I might kill the rose too (or I wouldn't be surprised if it killed JUST the rose, this stump is determined!) I pull/rub the foliage off of it almost daily and it won't die, after 3 years of doing that. I know I could take other measures, but at this point I'm kind of fascinated and am just seeing how long it can do that. I can keep killing it, I don't mind. Natural, if you put a pic of the plant that's troubling you, someone should know what it is. Are you having trouble with this weed in a lawn or bed? If you have just a few, sometimes a large rock can be the demise of a weed. Sometimes that just makes it come out of the side eventually. Check often because if it does, it can start producing energy again. If it pops back out, know it spent a LOT of energy finding the light again, and is now weaker. Move the rock, 'kill' it again, put the rock back. If it sounds like something you'd like to try if few enough plants (and plentiful enough rocks,) sometimes works the first time, sometimes takes a few tries to exhaust it, the bigger/flatter the rock, the better the chances. Feel free to start a new discussion, many who already looked at this and couldn't diagnose the original pic might not return to notice a new pic from a new person.

I would hazard a guess that it is a native Veronica species. Perhaps this one: Maryland Biodiversity Project - Common Speedwell (Veronica officinalis) Veronicas can be very pretty and providing it isn't conflicting with other plants in your yard I would personally leave it alone. I think yours has flower buds so you'll be able to see pretty soon if the id is close. Even if the id is wrong it seems to be an attractive ground cover.