Woolly Aphids on an Acer?

[Belinda]

Hi Everyone,

We have what look like woolly aphids on one of our Japanese maples  ???

Is this possible or is it more likely to be something else? If it is woolly aphid what kind of damage might they do and how can I get rid of/prevent them in the future.

All advice gratefully received,

Regards,
  Belinda

[Belinda]

[Merry Tiller]

Methylated spirit and a cotton bud  :'(

[beejay]

It may well be scale insects as I get them from time to time on my acers particularly on stem areas that have a little bit of damage. They quite often have white woolly stuff round them. I just rub them off.