Running along the Potomac Heritage Trail I passed numerous stands of these wildflowers:
What could they possibly be? After a few failed attempts with Google Image Search, I finally found a match:
And what do you know, they're Virginia Bluebells. Let's see: growing in Virginia? Check. Flowers shaped and drooping over like bells? Check.
Virginia bluebells have two interesting properties that contribute to their success as ephemeral wild flowers. Virginia bluebells form buds that are pink in color due to the anthocyanin (from the Greek anthos meaning flower and kyanos meaning blue) or colored cell sap that they contain. When the flower is ready for pollination, it increases its alkalinity to change the red pigmentation into blue pigmentation, a color that is much more attractive to pollinators. When the flower is pollinated and seed formation begins, it falls to the ground so that subsequent pollinators will only find those that still require their ministrations. The ubiquity of bluebells in their preferred riparian habitat (like Bull Run and the Potomac River Valley) is testimony to the success of their adaptations to attract insects.
So yeah, this plant is probably best served as a muse, rather than a trail nibble.