1 Iritis is uncommon, but can be due to trauma, infections, or autoimmune conditions. Symptoms include pain, red eye, and often, decreased vision.  Optic neuritis. The nerve travelling from the back of the eyeball into the brain can become inflamed.
Oak root fungus, or white rot, is a widespread disease that becomes visible just beneath the bark and on roots. What looks like layers of light brown to tan mushrooms form in clusters at the base of the trees.
Eventually, the apple completely decays, dries, and shrivels into a mummy. Pycnidia that contain spores of the black rot fungus appear on the surface of the rotted tissue. Disease Cycle The fungus overwinters in dead bark, dead twigs, cankers, and mummified fruit. It can invade almost any dead, woody tissue and frequently is found in tissue killed by fire blight. Early leaf infections often are visible as a cone-shaped area on the tree, with a dead twig or mummified fruit at the apex.