Merriam-Webster defines a weed as “a plant that is not valued where it is growing and is usually of vigorous growth.” That sounds about right. It’s easier to define what you mean by the word “weed” than it is to decide what qualifies as a weed. Some plants are easy—most of us consider dandelions to be weeds. Crabgrass and nutsedge are another pair that won’t get much argument. What about when it’s something you planted? If it gets out of hand, you might consider it a weed. We have a few things like that and this might qualify. Where we had two trees cut down we have a pretty vigorous growth of black-eyed Susans (Rudbeckia), purple vervain (Verbena bonariensis), and Virginia knotweed (a.k.a. painter’s palette, Persicaria virginiana var. filiformis). This picture is of knotweed, and we might need to start treating it as a weed. It is pretty, though, and more so with beads of water on the stems.