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I have 3 very large bay trees and 2 smaller ones put in about 6 years ago to act as screening. They are in quite a dry area of the garden and have large trees (sycamore and holm oak) near them, or rather above them. Due to the near 'drought' conditions here in North Norfolk I have watered them a bit. I have noticed today that one of the small ones is going very yellow and when I looked closely the bark on the trunk is covered with white stuff, like mould. I now see that the others have also got this white stuff on them. What is it and what should I do about it. Thanks for any help.

Mandy

Hello Mandy,

It sounds to me like it could be wooly aphid. Sorry we don't have any pictures of it on our site, have a look in google images, let me know if that is what it looks like. If it is wooly aphid, you could try spraying it with insecticide. Personally I would try removing it by gently rubbing with a stiff brush and some water. Or maybe if you think the trunk will take it, you could try using a pressure washer.