I am a very amateur gardener and I have an awful lot of what look like galls on the stems of my Forsythia (which is about ten years' old). I have looked this up on the web, but can't find a great deal of practical advice on how to deal with it. Must I destroy the plant, and can I re-plant another? How do I treat the soil if this is a bacterial infection? I read about a product called Galltrol and Gallex, but can't seem to find anywhere that sells it. I would be very grateful for some practical advice. Thank you.