What is this yellow/black bug on my sunflowers? Home › Forums › Flower-Garden Questions › Annuals and Perennials › What is this yellow/black bug on my sunflowers? This topic contains 0 replies, has 1 voice, and was last updated by Anonymous 8 years, 3 months ago. Viewing 1 post (of 1 total) Author Posts August 27, 2008 at 7:33 pm #28395 Anonymous hmmm- don’t think so. I saw some more pictures online that lead me to believe it is a Soldier beetle (and harmless). i am AMAZED at the number of bugs that can be in my garden! Author Posts Viewing 1 post (of 1 total) You must be logged in to reply to this topic.