A canker is similar to an
"open wound" on an animal. The are usually the result of
an infection an injury to the bark of a tree or shrub.
One common cause of canker disease in plants is the
fungus, Nectria cinnabarina. Otherwise healthy
plants will usually form callus tissue around the canker
and form a barrier that prevents the wound from
spreading. In weakened or unhealthy trees, the canker
may continue to grow and could circle and kill the
branch or even the main trunk causing death to the
plant.
The infected area
will become slightly sunken and discolored. Salmon,
pink or cream colored fungal fruiting bodies form in
spring to early summer. They are followed by red to
orangish-red structures in the late summer into
fall.
About the only way to
deal with cankers is to prevent them. Once the
fungus gets going, there is no other treatment. So,
avoiding injury to the bark of trees and other woody
plants is the only real approach. This means
avoiding pruning or other wounds especially in the
warm, wet parts of the year. Protect young trees
from freeze damage by using wraps where possible.
No treatments only
prevention.
Note: We
have provided some general information and
observations on this topic aimed at the home
gardener. Before you take
any serious action in your landscape, check
with your state's land grant university's
Cooperative
Extension
Service for the most current,
appropriate, localized recommendations.
