By Davidw
United Kingdom 
My two mature apple trees suffer huge attacks from woolly aphids. The insects seem to survive cold winters, emerging to colonise the trees in late srping. Insecticides based on thiacloprid, deltamethrin and even acetamiprid (intended for ornamentals only) seem just to encourage the aphids, either by acting as aphrodisiacs of killing competing orgabisms. The trees, formerly productive, are being seriously damaged. Any suggestions?
david W
20 Mar, 2011
Answers
You could try hanging bird feeders from the branches to entice birds who will also feed on the woolly aphids while they're there
20 Mar, 2011
I gave up my war with wooly aphids this years after a couple of years trying to eradicate them. I sprayed with all sorts, physically scraped them off and sprayed all last year every 2 weeks with Provado but to no avail - took the tree out a couple of weeks ago
I was told the best/only way is to scrub all the tree with methylated spirits...... on the bits I tried this it did make more of an impact than Provado but didnt eradicate them
20 Mar, 2011
Whatever chemical you use, mix it with a surfactant to get it through the "wool".
23 Mar, 2011
Previous question
products based on, or containing, pyrethroids or pyrethum are said to be the best treatment.
20 Mar, 2011