1. Japanese knotweed
2. commelina communis
3. weed...not sure of name
4. looks familiar...a keeper, I think, but I'm blanking.

Great work! I can usually figure natives out, but I have a hard time with invasives. if you think of that last one let me know. Here's the flowers I've ID'd in the woods so far, at least what I can remember:

Erythronium albidum (White Trout Lily)
Trillium grandiflorum (Large-flowered Trillium)
Uvularia grandiflora (Large-flowered Bellwort)
Arisaema triphyllum (Jack-in-the-Pulpit)
Podophyllum peltatum (Mayapple)
Sanguinaria canadensis (Bloodroot single and double-petal)
Viola sororia (Common Blue Violet)
Viola pubescens (Downy Yellow Violet)
Wild Ginger
Salomon's Seal
Interrupting Fern
Ostrich Fern
Elderberry'
Chokecherry
Fruiting Mulberry
Star Magnolia
Virginia Waterleaf
Virginia Creeper
Pink Dogwood

There used to be some Lady Slipper's according to the neighbors but I haven't seen any yet.
I also have another one I can't figure out. Not a great photo but it has burrs on it and it's pretty small.

If I'm not mistaken, that's the virginia waterleaf with its spent flowers. You've got excellent natives there, good for you. The trout lilies spread far and wide, but do disappear with the onset of summer. They will only flower when they have two leaves, and there are many many many (LOL) one leaved plants in the mix. They sometimes look messy in the spring, but I'm in love with these early natives.

I'll keep trying to think of that last one. Have you posted on the Name That Plant forum? You'd get an answer right away, most likely. And it's a much busier forum than this one.

Just remembered...Photo #4 could maybe be Actaea rubra Red Baneberry. Google and compare.

#1. Lady's thumb, Polygonum persicaria
#2. Asiatic Dayflower, Commelina communis
#3. I do believe it is Circaea lutetiana or enchanter's nightshade.
#4. Blue cohosh, Caulophyllum thalictroides

FataMorgana

Thanks all for the help! The little woods is really nice. It was planted in the 50's and was kept up nicely until the 90's when it started to get neglected. I've been doing a lot of work to get it cleaned up but there is a great base to work with. Here are some photos from this year:

Pretty sure your last ID request is white avens, geum canadense. Native, rather weedy.

Here is a link that might be useful: Geum canadense

I agree with FataMorgana on 1 thru 4, and yes, that is enchanter's nightshade.

The photo at the end of your post on Sat, with the mostly lower leaves, where the mature infloresences are burs.... I know that plant, intimately, over years, but I don't know the name of it. I will hope that someone can help both of us on that one.

I agree that the last one is a geum. I don't know G canadense but we have a very similar one, G urbanum.

Beautiful spring ephemeral natives. I struggle with Erythroniums and would love to have the right conditions for Sanguinarias and Trilliums.

Is the Polygonum persicaria considered a weed? We have it sprouting up EVERYWHERE here (garden beds, middle of the lawn, street gutters, cracks in sidewalks), and I've been pulling it out with a vengeance for fear it will take over everything.

Beatrice

What is a "weed" is one of the "eye of the beholder" things. Sounds like it is a weed to you!

FataMorgana

Hi Fata-so true! Someone told me impatiens are considered a weed in Hawaii because they grow so prolifically. But I love impatiens in my shade garden.

I suppose that if I could keep the Polygonum isolated to one location, instead of having one plant here, one plant there, one in every location where a plant is not desired, I could appreciate it more.

Thanks for the Zen insight. :)

Beatrice

Isn't the last one Actaea pachypoda, White Baneberry?

Last of the first 4 is Blue cohosh, Caulophyllum thalictroides. The last picture above has blooroot and troutlilies.

FataMorgana

So beatiful.but ����

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