"anton" wrote in message
...

Andrew wrote in message ...
Some lumps and bunps on an old apple tree have started to secrete a
white fluffy substance which looks like a mould to my untrained eye. How
concerned should I be? What action should I take? TIA.

Other posters have identified it as woolly aphid. Some trees
seem to have a little bit and not get further problems. It can
get out of hand later in the season, though, particularly on some
younger trees. Painting the affected bits with alcohol zaps the little
wotsits completely.

Or methylated spirits.

--
Brian
"Stuck down a hole, in the fog, in the middle of the night, with an owl."