Fungus On Hawthorn Hedge

[Tobermory]

I have noticed what appears to be white fungus on the stems in the hawthorn hedge here.



The fungus seems to be located around cankers.

Does anyone recognise this disease and is it likely to be detrimental to the hedge?

I will be happy to try to brush it or spray it with something suitable. It has only recently developed and is progressively spreading through the hedge.

[nickdub]

Can't make it out for sure - could it be woolly aphids rather than a fungus ? if you press your finger on those it looks a dark blood red under the white stuff - I use a brush and some white spirit if I get a lot on an apple tree.