Worcestershire,
United Kingdom 
my acer tree is covered in black fly what can i do
4 May, 2010
Answers
Many people have success by spraying weekly with very diluted washing up liquid - about one teaspoon of Fairy Liquid to a couple of litres of water.Although I have never tried this
4 May, 2010
it works, I did it last year when my rhododendron got covered with them.
this year i sprayed everything early..lol and checking daily for any signs of them.
5 May, 2010
Previous question
Spray with a product that treats for aphids.
4 May, 2010