Rhododendron periclymenoides

Deciduous azalea found in woods and along waterways. Formerly known as R. nudiflorum. Pink (to white or lavender) flowers are slightly fragrant and leaf bottoms have few hairs mostly on ribs. To distinguish from very similar R. prinophyllum, see https://gobotany.nativeplanttrust.org/species/rhododendron/prinophyllum/