Sycamore Maple Sooty Bark Disease

Sycamore maple sooty bark disease Common name Sycamore maple sooty bark disease Causal agent It is a fungal plant disease caused by members of the genus Cryptosoma. It is called sooty bark disease due to the appearance of black conidia when the bark falls away. Scientific name Cryptostroma corticale Symptoms & Signs The initial symptom of sycamore maple sooty bark disease is twig dieback which mainly affects young shoots and branches. The infection soon spreads to the heartwood, producing a light brown stain. It also affects the bark, producing black conidia called “Stomata.” During this process, it kills the bark, displaying the sooty stomata when the bark falls off.  Severely infected trees also show wilted leaves along with blisters and cracks on the bark. Transmission The black conidia on the bark contain fungal spores that spread via wind to other plants. High temperature and drought conditions favor the growth of this fungus. Time of concern Summer Common hosts Sycamore maple Horse chestnut Japanese maple Bigleaf maple