The photo is of a single Blue Mist Flower (Eupatorium species) about three feet high and six feet across. This plant is covered in baby blue flowers for about six weeks in the fall. It is an important butterfly and bee plant. This particular plant is growing alongside one of our greenhouses next to a vat we raise livefoods in.
Blue Mist Flower is common along fence lines, railroads, and roadways in Texas from Goliad south to Corpus Christi. I don’t remember it on our farm as a child, but it is very common now. I suspect cattle eat it since our north pasture, with its herd of Beef Master cattle, has little of it. While, our south pasture, home to five “eq-whiners” (beasts who complain loudly each morning if I’m late feeding them oats and which are often known as “horses” and “donkeys”) has large stands. Our two horses and three donkeys apparently prefer their daily oats rations and they don’t touch the Blue Mist Flower so it thrives. I consider it a weed in the yard since it will rapidly take over if allowed.
I don’t think Monarch Butterflies use it as a larval food because I’ve never seen their caterpillars on it, but the adults hang on the flowers. It must provide many of the calories the butterflies need for their annual migration through here on the way to the mountains near Mexico City where they overwinter.