The sunflowers are fascinating, not just for their size (and variations in size), but also the way wildlife interacts with them.

Yellow inchworm on sunflower
A nearly perfect disguise.
Bumble bee visits sunfloewr
Bumble bee pays one of the giants a visit.
Hummingbird docks at flower
Hummingbirds have found the sunflowers irresistible too. This bird casts a shadow on a leaf (lower right) as he docks with the flower's face.