This is tall blue lettuce. Flower color in this species ranges from white to blue, with many of those strongly suffused with yellow. The yellow combinations are interesting, and for a long time they were the only ones I've come across. The ones without yellow are not rare, I just hadn't seen them lately. One reason is that they're only open in the early part of the day. So it was a treat to see these at Oak Openings near Toledo. But the quest is not over. Still want to see full blue or pure white!