When looking through the 607 "Sunflower" images at Acclaim Images.com this Black-eyed Susan and Sunflower Blossoms Find Edges Filtered was a favorite.
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Description:
Black-eyed Susan and Sunflower Blossoms Find Edges Filtered
Stock image of black-eyed susan flower and sunflower blossoms extracted onto white background then filtered to find edges.

Some related terms for more images:
black eyed susans,  flower,  composites,  blossoms,  sunflowers,  filtered,  yellow,  summer flowers,  find edges,  beth conant,