ID based on INat suggestion
I looked at this plant on 5-9-24, and it was covered with pollinators of various kinds. I submitted photos of a bumble bee and a lady beetle from that day to iNaturalist. In today's observation, the flowers were past their prime. There was a light breeze today.
The tag by this plant is labeled "Little Flower Penstemon"
I did see one bumblebee on a B. Sagittata just as I was approaching the site, but it flew away and although I waited a long time at various plants for one to come, I had no luck.