Discula destructiva

Commonly known as  anthracnose disease

Description:  This introduced pathogen affects Cornus nutalii the most.  It can hide out on twigs and branches during the winter, producing brown fruiting bodies.

Identification:  Distinctive brown splotches on the leaves will appear in infected trees.

Hosts: Various Cornus species, including cultivars.  In our area it can be seen on Pacific dogwood.

Distribution: Widespread in western Washington

General Information:  This pathogen was introduced to Washington state in the 1970s.  Since then it has wreaked havoc on the Pacific dogwood.

Sources:  Arno, Stephen F., and Hammerly, Ramona P.  Northwest Trees, revised edition.  1997.