I had to chime in! In the South (US) we call that a poke sallet bush. Yes, it is edible, BUT only the leaves and for a limited time. You have to find a plant early when the shoots (leaves) are new. Here’s the rule "once it starts turning red, it will kill you dead". The plant even has its own song "Poke Salad Annie". At one time you could purchase pre-cooked poke sallet in a can at the grocery store. It's cooked much like you would cook turnip greens or collard greens. I have one of my grandmother's old cook books from the 1930's and it has several recipes listed using poke "greens" Every bird known around here eats the berries, because just when you get your car washed, along comes a bird and poops purple on your car. As well as birds, raccoons, opossums and foxes will eat the berries, Apparently they are immune to the toxic chemicals. Poke sallet bushes are deer- resistant. Some kids would eat a five to ten berries on a dare. It didn't bother them, but they will turn your urine and poop purple. If you ate a lot of berries I'm sure you would get a terrible tummy ache. Native Americans used the roots to make a liquid and applied it to the skin to stop itching. While I haven't kept up with the studies Poke sallet antiviral protein PAP has been isolated from the plant. PAP is being tested to hinder the HIV virus in humans. It is being studied for possible therapeutic use for T-cell leukemia, lymphoma, and Hodgkin's lymphoma. Why would anyone eat it? Thanks to the critters that eat it then leave behind a poke seed, it’s multiplies fast and is everywhere. Poke sallet became one of the major food sources for the extremely poor living in the rural South. If you’re hungry and penniless, you’ll eat just about anything.

It will be helpful. I have this weed in my garden and pots.

Difficult to say what it is as much of he plant is obscured by grass.. You could dig up an entire plant and take it to the local agricultural agency or turf specialist. If that sort of resource isn't variable in your area, after you dig up an entire plant, set it on a plan background, take a picture, and post the image here.

.... which is a common name for Lespedeza cuneata, as identified three years ago.