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.
The fruiting bodies of fungi grow on wood chips, shredded bark and other mulches, and the resulting mushrooms may look unsightly but are mostly harmless. Fungi help break down dead organic matter, providing nutrients for plants. The mushrooms they grow emit spores that spread the fungi to new areas.