White Polygonum orientalis L. (Kiss-Me-Over-The-Garden-Gate)

I live on an ex-farm (the land was subdivided and all we got was 1-1/2 acres and the barn) and there are polygonums growing wild all over the place and up and down the street I live on. Most are in the shade and only grow around a foot tall. I like to bring a few up into my garden every year where, in full sun, they grow 3-4'. This year I have an "albino" one growing! I've never seen white ones, and after a google search, can't come up with them either. Have any of you seen them? I'll definitely save seeds this year!

I don't know anything about them. Doing a search on them doesn't bring up much, except to say it's not an indigenous plant, it's an introduced plant. It's in the genus of knotweed and is considered weedy according to the USDA site. Sorry! Thought you might like to know.

Bad news, Polygonum orientalis is not indigenous/native to your state or even to anywhere on the continent of North America. It's an introduced/exotic species that is documented as having "naturalized" in 36 states which isn't good at all for the plants that really are indigenous/native. Some people refer to it as a noxious weed while others refer to it as an invasive species for just the reasons mentioned by you, "growing wild all over the place and up and down the street I live on".

It is a pretty plant though. I don't know that you would be interested but they pull out by hand easily enough.

Also worth mentioning that there are quite a number of white-flowered Polygonum (some of which are native), and that members of the genus can be difficult to tell apart. Good odds that your "white Polygonum orientalis" isn't Polygonum orientalis.

Patrick

I enlarged her photo and that is no orientalis like what I've seen and yanked out of the ground before. P. orientalis has leaves that are ovate. Her plant sort of looks like my P. hydropiperoides that I bought to plant out in my wetlands but the leaves on her plant aren't linear enough. I'm looking at the plant she photographed and it's looking a lot like a white flowering pensylvanicum. Those are incredibly aggressive around here and I try to whack them back but I've never seen one bloom white like that. Are there any white flowering pensylvanicum instead of the range of pinks I've seen it in or is that some sort of a sport? You know plants way better than me. What do you think she's got photographed above?

Well, my first thought it that this is Polygonum lapathifolium, but I'm not sure if that's just because it's the common one out here in New Mexico that looks more or less like this. I haven't looked at northeastern US Polygonum in a while, although a quick check shows P. lapathifolium does grow in MA. If I had it in hand I'd count petals. P. lapathifolium has four, the similar species (that I've seen, anyways) all have six.

Patrick

Doesn't lapathifolium have alternate leaves?

Just did a search. Several notations that they normally have alternate leaves but can have opposite. Guess it's petal counting time!

Eh? The plant in the photo has alternate leaves, I think.

Patrick

Borrowing her photo for a moment. This is what I was looking at-

Ah. Looks like those are just secondary stems coming from the axils of the primary leaves. The secondary stems have two small leaves each; harder to tell on those, since the stems are so short, whether the secondary leaves are alternate or opposite (the front one looks alternate, the back one looks opposite from here, but would probably turn out to be alternate on closer inspection), but it's clear the primary leaves are alternate.

FWIW, you can see this phenomenon more clearly (on Polygonum maculosum, FWIW) here:
http://www.polyploid.net/swplants/images/Persicaria_mac_7-1105_0147.jpg

In that case, the secondary stem has three leaves and several inflorescences, but if we imagine it a little earlier in its development, with only two leaves, we have the situation seen in PrimroseSue's photo.

Patrick

OK, I understand now. For me, it's so much easier having a plant in front of my face with somebody explaining but a good close up photo helps too. I tried to see in her photo where the larger leaves "connected" to the stem and couldn't really get a take on them because when I enlarged her photo and used a magnifyer, it got even grainier. I really couldn't see much other than that the larger leaves might be alternate but those little secondary stems did look opposite to me. Really thought those were leaves from her photo. The photo you posted is good.