Anthracnose—and canker are general terms for a large number of different plant diseases, characterized by broadly similar symptoms including the appearance of small areas of dead tissue, which grow slowly, often over a period of years. Some are of only minor consequence, but others are ultimately lethal, and of major economic importance in agriculture and horticulture. Different cankers and anthracnoses are caused by a wide range of organisms, including fungi, bacteria, mycoplasmas and viruses. The majority of canker-causing organisms are tied obligately to a single host species or genus, but a few will attack a wider range of plants. Canker can be spread by weather and animals, making an area that even has a slight amount of canker hazardous.
Some cankers are treatable with fungicides or bactericides, but many are not; often the only treatment available is to destroy the infected plant to prevent the disease from spreading to other plants. Managing the disease with fungicides will help to prolong the life of the tree.