Darn, I hate to hear that !! It's unusual to find more than one borer in a rhizome...but even one is too many ! I would say that any insecticides you use would have to be "systemic', and then they are only effective while the borer is actually "eating". As MaryAnn said, depending on the size of the bed, a very close inspection of each plant, 'manually" killing / removing the borer, and treating for rot may be your only choice. Good Luck..........Arlyn
