Correction Hemp Dogbane instead of Milkweed growing in James Hunter Park in Arlington, VA
Swallowtail
(Hemerocallis fulva)
AKA Tawny Daylily, Tiger Daylily, Fulvous Daylily, Ditch Lily, and other names.
Oddly, it's really not a lily as it spreads via rhizomes. Native to Asia, considered invasive by most.