buttonbush
Cephalanthus occidentalis

Hardiness: Zones 5 to 9
Plant type: Shrub
Height: 5 - 12'
Spread: 4 - 8'
Sun: Part shade to full sun
Water: Medium to high
Bloom time: June
Bloom color: White
Soil: Clay-based, moist, organically rich soils, loamy, average well-draining soils, sandy, well-draining soils, acid (<7pH).

Notes: Wildlife food source, enjoys wet open areas, low woods, thickets, swamps, upland ponds, river bottomland, stream/pond margins.

More info on this plant found here.