Treatment: Remove all infected plant material to slow spread. The foliage of the diseased limbs turns yellow and dries. Caused by the fungus Taphrina caerulescens, oak leaf blister manifests in light green spots around 1/4 to 1/2 inch in diameter on ... Armillaria Root Rot. Severe infections may cause foliage to be malformed and can lead to early leaf drop. With some varieties reaching heights of 100-feet, oaks need to be handled carefully and skillfully. A warm, humid summer can cause fungus to grow on your otherwise stately, beautiful oak trees. Copyright Leaf Group Ltd. // Leaf Group Lifestyle. If you haven’t been able to remedy the issue in one or two growing seasons, and the disease is one that will ultimately kill the tree, it’s time to bring in support. It affects the leaves, leaving spots, and causing mostly aesthetic damage. The majority of people can agree that oak trees are beautiful. Eventually, branches and twigs die altogether. Remove infected trees and protect healthy ones from stress. Branches die back, and a firm, honey-colored mushroom forms annually in … Symptoms: Circular, dark to reddish-brown spots on the leaves; can run together creating blotches. Some discoloration. Treatment: In general, pruning dead twigs and branches during dormancy is the best treatment. If oak root fungus is identified, remove the soil from around the root crown to expose and dry out its roots. Uproot afflicted trees and dispose of them immediately to prevent spread. It starts with fall coloring out of season—the leaves are wilting and browning, and within a few weeks, the tree is dead. The fungus infects the inner bark causing the outer bark to slough off. Symptoms: Honey-colored mushrooms form annually at the base of the tree. Post, water, southern red, white, and blackjack varieties are most likely to develop this disease. She has an A.A. in journalism and a B.A. The disease reduces property value as trees die and the property owner must pay for tree removal.Additionally, preventing the spread of the disease to healthy trees is costly and requires vigilance. Causes: Many different bacterias cause this as they enter the tree through wounded bark. Unusual shapes. Others, though, indicate immediate removal. Remove infected trees quickly and inject neighboring oaks with a fungicide to inhibit spread. Season: Infection occurs at any time, and severe damage becomes noticeable in summer and early autumn. All oaks, as well as many plants and vegetables, are prone to this infection. For severely damaged arbors, particularly those that are prone to windthrow and breakage, it is always best to seek out a licensed, insured, and experienced tree care expert. Symptoms: A white growth on the surface of the leaves, both top and bottom. Season and Risk Level: All varieties of oak are susceptible, and damage will appear in late summer and fall. When they are afflicted by disease, they lose all of their aesthetic appeal. Causes: Fungi enter through wounds in the bark, including pruning injuries. These growths appear in large groups and are followed by a white fan of fungal growth under the bark at the base. Several oak tree diseases are caused by fungi. Walk around the affected oak experiencing slow growth and look for callus-covered wounds and cracked bark to... 2. However; it can be treated. Risk Level: Most species are susceptible. Plan the perfect garden with our interactive tool →. Promptly remove and dispose of infected trees, and grind stumps to prevent disease spread. Causes: Iron chlorosis takes hold during wet, humid, and mild conditions, typically as buds break. The third method to get rid of tree fungus is using a bleach solution.