Maple Diseases

Maple: Anthracnose

Maple: Anthracnose categories: Maple Maple Diseases Ornamental trees Ornamentals last review date: 2025-07-07 09:56 Maple anthracnosePhoto by: R.S. Byther Biology Maple anthracnose is a fungal disease affecting leaves and sometimes twigs. Infected leaves develop discrete brown spots and/or blotches, often at leaf tips and often associated with the main or secondary veins. Japanese maples tend […]

Maple: Bacterial leaf spot and dieback

Maple: Bacterial leaf spot and dieback categories: Maple Maple Diseases Ornamental trees Ornamentals last review date: 2025-07-07 10:12 Pseudomonas leaf spot on maplePhoto by: R.S. Byther Biology Bacterial leaf spot and dieback is caused by the same bacterium which causes bacterial blight of lilacs and many other woody ornamentals. Symptoms include leaf spots, blackening of […]

Maple: Fasciation

Maple: Fasciation categories: Maple Maple Diseases Ornamental trees Ornamentals last review date: 2025-07-07 10:12 Fasciation showing a flattened, twisted, ribbed stemPhoto by: R.S. Byther Biology Fasciation is a plant deformity which results in abnormally flattened stems. It is the result of a mutation in the growing point of the stem and is not a disease. […]

Maple: Nectria canker

Maple: Nectria canker categories: Maple Maple Diseases Ornamental trees Ornamentals last review date: 2025-07-07 10:14 Tubercularia canker fruiting bodiesPhoto by: R.S. Byther Biology Nectria is a fungal infection which often attacks via wounds and forms cankers on twigs, branches, and trunks. The cankers are often sunken areas that develop conspicuous yellow to orange-red fungal fruiting […]

Maple: Phyllosticta leaf spot

Maple: Phyllosticta leaf spot categories: Maple Maple Diseases Ornamental trees Ornamentals last review date: 2025-07-07 10:15 Biology Symptoms of Phyllosticta leaf spot on many maple species include the development of small (approximately 1/5 inch), roughly circular, brown spots with dark reddish or purplish borders. Japanese maples develop yellowish or tan spots, which sometimes have transparent […]

Maple: Powdery mildew

Maple: Powdery mildew categories: Maple Maple Diseases Ornamental trees Ornamentals last review date: 2025-07-07 10:16 Powdery mildew on maplePhoto by: R.S. Byther Biology Powdery mildew of maple is a fungal disease which affects many hardwoods including maple, hazel, birch, and alder. On maples, a characteristic white, fuzzy or powdery growth appears on the upper or […]

Maple: Tar spots

Maple: Tar spots categories: Maple Maple Diseases Ornamental trees Ornamentals last review date: 2025-07-07 10:17 Maple tar spotPhoto by: R.S. Byther Biology Tar spots are caused by a fungal infection that commonly attacks bigleaf maples and occasionally other species. In late spring to early summer, leaves develop small areas that appear water soaked. The areas […]

Maple: Verticillium wilt

Maple: Verticillium wilt categories: Maple Maple Diseases Ornamental trees Ornamentals last review date: 2025-07-07 10:22 Verticillium wilt on small maplePhoto by: R.S. Byther Biology Verticillium wilt is caused by a soilborne fungus. It infects plants via the roots and then spreads throughout the plant. Symptoms on the aboveground portion on the plant include suddenly wilted […]