an issue with my acer tree
I have what appears to be a white moldy growth with brown spots on the stem & branches of my tree. It is soft to touch and appears to just rub off with no apparent damage to the tree. What is the best way to treat this please?
Sounds like it might be powdery mildew, https://www.gardeningknowhow.com/plant-problems/disease/get-the-cure-for-powdery-mildew.htm
To be sure, you need to have a knowledgeable person examine some samples. This link will help you locate one: http://mastergardeners.org.uk/get-involved/find-your-nearest-master-gardener/