Well, they ARE both Lamium. I didn't look up the botanical name of Dead Nettle or I would've realized that. And yes, henbit is smothering lawns all over the place here as well. Or maybe it is dead nettle ....

Looks like verbena bonariensis to me, but then my (occasional) IDs have been off the mark lately :-) Gary

It is indeed a Thistle, and I would suspect it of being Field Thistle, Cirsium discolor (Muhl. ex Willd.) Spreng. Field Thistle link. (That Latin mess is just the Scientific name along with the guy that named it) or a Carolina or Soft Thistle, Cirsium carolinianum (Walter) Fernald & B.G. Schub. Carolina Thistle link. Both have lovely flowers, inhabit old fields, and unfortunately, lawns (OUCH!), and non-birders blame people who feed birds with spreading them through "thistle" seed in bird feeders, but that "thistle" is an African plant called "Nyjer", and cannot grow here. Goldfinch are closely tied to Thistle; they do not start breeding until it blooms (July and later), make their nests out of the fluff (so tight they hold water!), and eat the seeds, and feed the seeds to their babies. They are so closely tied that their scientific name of "Carduelis" is very close to that of most Thistle (Carduus).

Mine is already yellowing and dying out here because we've been in the mid- to upper-80s all week. I am not crazy about how invasive henbit it, but leave it alone until it starts dying back because the bees and other pollinators and beneficial insects need it at a time when not much else is blooming. Here where I live, it is one of the earliest signs of spring. Ours has been blooming since February and is dying back now. By the time it dies back, lots of other spring bloomers are in bloom for the bees and pollinators. Once the foliage is yellowing, I pull it out of flower beds and mow it down in the yard. I don't let it grow in the veggie garden. Since the veggie garden is heavily mulched, it never has been much of a problem there because of the mulch. Any henbit that pop up there or in the strawberry beds, which are in a separate area, gets pulled right away. Dawn