Penstemon hirsutus, flower. C & O Canal Park, Montgomery co., MD. (4/26/12)
The USDA Plant Database assigns these to the Scrophulariaceae family, but the APG III classification system now places them in Plantaginaceae.
I had some trouble with this genus, and I changed my initial species ID for these plants. I am confident that this is the correct one.
I only found one small community of these, growing out of fertile soil between big rocks in a sunny place along the river. Their vibrant beauty seemed to leap out at me. They are covered with sticky glandular hairs. Some tiny insects that had gotten stuck in it had died there.