I have the leaf cutter Bee in my garden and find them fasinating, they do no harm to the flowers just cut a beautiful circle out of a leaf, I put a bee box on the house wall , the one with the canes inside, and love watching the busy Bees going in and out, they lay there egg, put a blob of honey in for the grum to feed on then seal up the cane with the cut leaf, then next spring the " Baby " grows and hey-presto a new baby Bee,
NEVER,NEVER use PESTICIDE, you will kill all the Bees etc,