By 439
United Kingdom 
My son has just moved house and in the garden is an apple tree with a lot of what looks like funges on the trunk and branches, the previous owner was an elderly lady who i imagine did not do too much to the garden
15 Jun, 2012
Answers
Welcome to GoY:
There is no problem here at all that is Lichen and harmless to the tree. Take a look in any park or garden and all the older healthy trees will have this to a degree. Sit back and enjoy the apples.
Nice photo as well.
15 Jun, 2012
Can be scrubbed off with mild soap and water if your son doesn't like the look of it. Much more frequent on very mature woody plants.
15 Jun, 2012
It is lichen and will not do the tree any harm. They say that having lichen is a sign that the air in your area is fairly free from pollution.
15 Jun, 2012