I haven't been able to confirm whether Hydrangea arborescens is a true North American
native, or naturalized.
Identification: These hydrangeas are shrubs that reach 3-5′ (91-152 cm) in height.
The Annabelle variety is the most widely known, producing large white flowerheads up to 8-12″ (20-30 cm) across.
Leaves are dark green, wrinkled, 8-12″ (20-30 cm) across.
Hydrangeas are popular with gardeners. Common in foundation plantings and landscaping, colored varieties
have been developed as well. See this Hydrangea comparison table.