Fruit Tree Fungus

I think they are a polypor fungus.. Did your tree get stressed in all the dry weather, a split or any damage to the bark.? The fungus itself doesn’t become active until the tree is diseased or stressed. Others establish themselves where a tree has been damaged – on the end of a broken branch, perhaps, or through a gouge in the bark.
Most tree fungi consume decaying wood, but there isn’t a lot of that on a healthy tree. So some species cheat by giving out chemicals that cause rot in the surrounding wood. That gives the fungus a steady supply of food but eventually the infected branch or trunk will become brittle.. You can also spray the tree with a fungicide, such as Bordeaux mixture. It might help perhaps.. Regular sprays when buds are swelling, and again when the tree flowers, can help prevent infection. Is it an old tree.?