Common Tree Diseases in Oklahoma
Common Leaf Diseases
Common Diseases of Conifers
Dothistroma Needle Blight of Pines-
Sudden Oak Death-
affects the leaves, shucks, and twigs of the infected plant and manifests as small (1 to 5 mm), circular, black or olive green lesions. Scab fungus (Cladosporium caryigenum) invades young, rapidly growing shoots and leaves and later the developing nuts. Pruning to open up the tree for better air circulation will help reduce scab occurrence by reducing the number of infection periods occurring during the year. Good sanitation practices may help prevent the disease. Removal and destruction of all fallen leaves, shucks, and nuts each winter or early spring helps reduce tissue that is often involved in the primary infection. Also, selective pruning of infected tissue during the dormant season may help reduce the level of scab disease.