Informational table showing disease name, symptoms, pathogen/cause, and management of Catalpa diseases. Disease Symptoms Pathogen/Cause Management Leaf spot Brown to black spots form on leaves. These spots may drop out or leaves may fall prematurely. Many different fungi can cause spotting. No control is recommended since little damage occurs. Powdery mildew White fungal growth develops on the upper surface of the lower leaves. Microsphaera or Phyllactinia No control is recommended since little damage occurs. Verticillium wilt Purplish to bluish-brown streaks are found under the bark in the sapwood of wilted branches. Wilting often develops on branches on one side of the tree. Verticillium Trees may die within a year or may survive to wilt to some extent every year. There are no effective controls. Do not replace a tree killed by Verticillium wilt with another catalpa or other species susceptible to the disease.

Verticillium wilt

Discoloration by Verticillium

Prepared by Gary W. Moorman, Professor of Plant Pathology