Gardeners, help needed regarding a Ballerina apple tree

I have an apple tree which grows to about 10 feet tall and the branches are very short, it is called a Ballerina tree, I don't think there are a lot of this variety about.

Today we found little clumps of white fungus growing on the trunk, the fungus type of stuff rubs off easily but when it is wiped away there is a red juice underneath which is just like blood, it stains your fingers until it is washed off.

Does anyone know what it is, what causes it and most importantly what can be done to get rid of it.

I would welcome any advice on the problem as it is a lovely tree and the apples it grows are delicious.

I think it's woolly aphid.

I've had it on my apple trees from time to time,it's a nuisance but not serious,you won't lose your tree.

Here's some advice

https://www.rhs.org.uk/advice/profile?PID=724.