Sudden Oak Death and Associated Diseases Caused by <i>Phytophthora ramorum</i>

Fig. 9B. Infected rhododendron leaves have dark brown lesions. Necrosis is often concentrated along the midvein in leaves infected from a twig infection via the petiole. Leaves infected without prior twig infection can have leaf spots on any part of the leaf surface.



Image from Plant Health Progress article:
Sudden Oak Death and Associated Diseases Caused by Phytophthora ramorum