Spent an hour at the site last week, and got lots of photos thanks to Karen Bennett's keen eye! Beneath the black landscape fabric, the knotweed seems dormant if not dead. One very sickly little tendril had squeezed up through a tear in the fabric, but there seemed to be no new growth poking up from below.
The few stalks growing up in-between the seams of the pieces of fabric were narrow, no thicker than a pencil.
I am amazed at the response of the poison ivy ~ it is all over the site, growing vigorously under the knotweed's canopy along the edges of the landscape fabric. There are a number of other hardy plants keeping it company, but I'd venture to say the knotweed site is currently "owned" by poison ivy.
We could positively identify Queen Anne's Lace (delicate, carrot-like leaves ~ NOT triangular, like Wild Chervil! ~ and a tiny purple blossom in the middle of each flower cluster. We also noted some soapwort and goldenrod, as well as the determined sumac trees.
Other plants are on site and we could really use your help identifying them!