Can you identify the beetles on my sweet acacia and tell me what to do about them? For perspective, the trunk is only about 1.5-inches in diameter. The beetles are about a third the size of a ladybug.

A: These are actually plant bugs of the order Hemiptera rather than beetles. You can see two adults at the base of the tree in the photo. They are grayish with an orange border. The blue and red ones are the nymphs or immature bugs. Their common name is bordered seed bugs or bordered plant bugs Largus cinctus. They are typically found in large numbers like that and although they might look threatening, they do very little damage. I would not recommend worrying about them or trying to manage them.

Peter Warren is the urban horticulture agent for the Pima County Cooperative Extension at the University of Arizona. He works with landscape professionals, urban farmers and homeowners to promote integrated pest management and best management practices for desert horticulture in southern Arizona. Questions can be sent to