It is a disease generated by various types of fungi, especially from the genes. Colletotrichum and Gloeosporium. It affects many ornamental trees, almost always on the leaves, although in adult specimens it can cause bumps on the trunk. The spots generated cover the veins of the leaves, which are deformed, and in the case of young leaves, they die and fall, constantly weakening the tree.

The fungus that causes this disease reproduces, which is dispersed by the wind and reaches the leaves, on which it spreads, in the form of white powder that will prevent the nutrition of the areas of the leaf that it covers. It attacks species as common as the plane tree, the catalpa, oaks…. The main sign is the appearance of a layer with a floury or cottony appearance and a white or grayish color, formed by the mycelium and the conidia. It will also cause the deformity of the growing leaves. In a strong attack the leaves turn yellow and later dry up.