The commoner orange-flowered Impatiens capensis grows everywhere in Fern Valley (and everywhere in the Washington area where there's moist soil and some amount of shade). The yellow-flowered species is less frequently encountered, though it occurs throughout the Eastern United States north of the Gulf Coast. Both species are regularly frequented by Hummingbirds and nectar loving insects that can reach down into the flower. In spite of the common name "Touch-me-not"), the sap from both species is used to counteract the effects of Poison ivy. Like the common garden flower Impatiens, when their fruits mature, they dehisce explosively sending their seeds flying. Running the length of the back terrace of Senator Rockefeller's Washington residence there was a spectacular 100'+ bed of mixed impatiens. Water can trigger this explosive dehiscence; I remember hand watering and as I moved down the bed I would hear hundreds of fruits "popping" open.
This stand of Pale Touch-me-not represents the progeny of plants grown from seed collected by ex-FV staffer Hannah Mullen, who brought back seed from West Virginia a few years back. We got no germination initially, but saved the seed tray an extra year and a few seedlings appeared. Because the plant is an annual and could potentially be cross pollinated by Jewelweed, we looked for a site without existing Jewelweed but still culturally congenial. The plants ended up alongside the road near the end of the petroswale below the Pawpaws. It must have been a good choice because here we are next year with a lush colony of Pale Touch-me-not!