Bridgend, United Kingdom

I have three bay trees in pots, which I have had for some years now, without any problems.
Having recently lightly shaped them, I have noticed that 2 of them have the new leaves tightly curled up and covered in what looks like dandruff !! its not white fly.
The leaves are sticky.
Anyone know what this is, and how it should be treated.
Many thanks.

• 21 Jul, 2014