That doesn't sound good. Could you post a picture of the area the weeds are growing in? From what you say, you will see another one pop up soon.

Here's a photo of where they're growing. (You can see the shovel marks where they were dug up).

I saw that Ken said maybe pokeweed in the other thread, and that could be, but I was thinking of other things that pop up from a mass of roots; pokeweed usually has one massive root per plant. Could you give a clear picture of the next one that pops up, when it is still in the ground?

Thank you for your feedback.

Yeah, I posted it on the "weed," "name that plant," and "Nevada gardening" (though I doubt it's only a NV species) threads of this forum because I wasn't sure how many people would see it and I wanted to get as much feedback as possible. I'm sure there will be some more of this stuff break ground over the weekend, if not tomorrow, so I'll take a photo of it in the ground and make sure I hold my hands steadier this time so the shot is clear. I literally scour the ground and get out the shovel as soon as this stuff breaks the surface.

It's odd because I haven't seen that weed on the side of the road or at parks or anything like that. I even checked the noxious weeds guide for my area and didn't see a photo of it. But maybe I've seen the full-grown version of the weed and I'm just not aware. Maybe it looks entirely different when mature versus when it's just starting out.

Could you post another photo in focus. I can't make out any detail on the plant above.

The stuff is back again today! Here's a more focused photo of the weed in the dirt. Any ideas on what it might be? I'm bewildered.

What I can't figure out is how something that is such a fast grower with, as you said, lots of roots, could just show up. Was there something growing in that area last summer? Is this your first spring in the house?

I moved to this house in June 2014, so technically it's my first spring here. When moving in last year, I pulled up the weeds in that area but it was mostly thistle-type weeds and if something would reappear, I'd pull it and spray. But nothing like this. Nothing else was growing in that area except the plants around the perimeter, which were supposed to be there. Here's another photo of them dug up if that helps. Thanks.

Someone on the "name that plant" thread said it might be Japanese knotweed. By looking at photos online, they might be right. I read about the stuff and it's pretty scary. I'm doing everything I can to dig it up as soon as I see it. I've sprayed Ortho Weed-B-Gon, but I need to get something that contains glyphosate. Those do-it-yourself sprayers have such a tiny hose, though, and it's hard to cover an entire area. Ugh. Maybe it's time to call in the professionals.

Carla, one of the great botanists over in Name That Plant just posted that she thinks it is Japanese knotweed, which is what I was afraid of. Someone else suggested to let one shoot leaf out, to make identification easier, which I think you should do, so that you can be sure what it is. Here is a page on the horrible Japanese knotweed:
http://en.wikipedia.org/wiki/Fallopia_japonica

and another : http://www.invasivespeciesinfo.gov/plants/knotweed.shtml

I hope that we're wrong.

Hey Lisanti,

Thanks. I went out in the rain (the drought-stricken desert is actually getting rain today!) a few hours ago and dug these up again. They'll probably be back tomorrow or the next day, though. I'll let a leaf or two grow on one of the plants just to get a better look at it. I'm wondering if some seeds blew into the yard? So odd.

That's what I just don't understand. You would have had to notice it last year, new house or not, as these things get tall. I know they grow like crazy, but this just doesn't seem like a one-year old plant. It's a mystery, and that's why I am hoping we're all wrong, and that it's something else altogether.

It definitely wasn't there last year. Is it possible that seeds could have blown into the yard a few weeks ago and they're just getting started trying to grow?

I am 99.9% positive it is knotweed. This is everywhere in my area and I've seen it in all its permutations. The seed might have migrated over last season or a new plant can generate from just a small section of root or stem. This is actually a more likely occurrence.

And forget the glyphosate - this stuff just laughs at it. Get something with Triclopyr in it - usually labeled as brush and vine killer.

If there was knotweed there last year the old stems would be standing 6 feet tall all over the area. Unless someone levelled the ground and removed the old stems. if they did and there is knotweed there I would think you have grounds to claim some kind of compensation for the deception. It's like selling you a house with concealed asbestos. Banks over here won't lend to buyers if a home has JK.

Or have you had a load of soil delivered? Knotweed could have come in with that. JK doesn't set seed over here - all infestations are caused vegetatively.

Post a picture of a full leaf and we can be certain.

I have read some horror stories online about that issue in the UK. This is much worse than dandelions.

There's been no soil/dirt delivery here. If the ground was leveled last year before moving into this house, wouldn't the Japanese knotweed have returned shortly after it was cut? From what I read, it can take repeated applications of herbicide to get this stuff to go dormant...and it doesn't stay dormant for that long. I don't know if home inspections here include knotweed and invasive plants. It's something I need to look into.