Flower clusters of the wild Hydrangea, Hydrangea arborescens, in McCurtain County, Oklahoma. The flowers with large petals are sterile, while the numerous apetalous ones are fertile. This shrub of damp forests can be found over a large portion of the eastern US, and many garden-worthy cultivars have been developed. The mating beetles on the left are flower longhorn beetles, Typocerus velutinus.