I've just noticed several inches of whiteness on a lower branch which still has leaves further along. I've never noticed this before & wonder if it could be a fungus & if so, how can I be sure & how can I treat it? This was once a pink/green/white leaf variegated tree but now has all green leaves having exhausted the original acid soil we planted for it; there are sycomores & birches in the area where we live but the soil is quite heavy with clay deeper down. The tree is about 15 years old.
Unless the bark is showing signs of peeling or damage it's unlikely to be a fungus. Perhaps it's lichen?
There has always been lichen on the tree but it's silvery grey & textured. This is as if someone has taken a 2 inch paintbrush & painted about 8 inches of a branch on the inside where the outer bark seems to have come away as we see in some small & large acers. I tried chipping it off with my nail will little success.
Do you have squirrels? They will strip bark in winter, and can cause a lot of damage.
I hate grey squirrels knowing they've driven out our reds & yes they're around here though I've not seen them strip that branch I could have been at work then/when they did it I'll google this white stuff!!