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.
These tree trunk infections called burls look like bumps or warty growths probably caused as a result of environmental injury. Cambial growth is hyper-stimulated as a way for the tree to isolate and contain the injury. Almost all burl wood is covered by bark, even when underground.