Strange things on my acer's bark
By Liz10
United Kingdom 
My acer has recently developed sticky adhesions on the bark. They are brown, about 2-3 ml across, oval-ish shaped, like miniature wood lice. They are stuck to the tree with white sticky substance in cells. What are they, what do they do, and what should I do?
1 Jun, 2010
Answers
Sound like mussel scale. These are apjhid like sap sucking insects. Use a horticultural soap and scrub them off without damaging the bark of the tree.
1 Jun, 2010
Snap!
1 Jun, 2010
Thanks folks. I think I have hours of work ahead of me as there is a lot of it. Really appreciate speedy responses and advice.
1 Jun, 2010
Sounds like scale insect - cotton buds dipped in methylated spirits and applied to each one, otherwise, think Provado might make a treatment spray, not sure.
1 Jun, 2010