We have a few very large, established Linden trees in front of our house. They are so badly infested with aphids that the resulting stickiness makes the (considerable) space underneath the trees unusable. They are scheduled to be removed this spring! Is there any effective alternative to their removal? We have tried bringing in ladybugs (lady beetles) for several (two?) years running to no measurable effect.
A systemic insecticide may be a beneficial solution. Unfortunately in Vancouver there is a pesticide ban so you cant use any products that you might be able to get your hands on of this nature. If it is worth it to you try contacting a large tree care firm such as Bartlett or Davey, as far as I know trunk injection is still allowed as a pesticide application method, they may be able to provide this service for you. As for a chemical, consider dimethoate aka Cygon 2E.
