| I don't think I can cure your problem but you aren't the only one. I rarely spray for greenfly, and it isn't really practical to spray something like a silver birch. Give them a few weeks and ladybirds will breed enough to control them. You might wish to keep ants out of the tree since they will attack predators to protect the greenfly. |
Here is a link that might be useful: BBC news story about the greenfly invasion
