WHAT IS IT?
Cytospora Canker is caused by a plant pathogenic genus known as Leucastoma kunzei. Cytospora Canker is one of the most common stem diseases in North American for coniferous trees.
Cytospora Canker can infect several different genera of coniferous trees. Among these are several species of fir, spruce, and larch.
HOW TO IDENTIFY:
The first symptoms of Cytospora Canker is usually a browning of needles and dying of the lower branches. Eventually as the disease progresses the higher branches begin to die off. The cankers themselves are typically not obvious to see because the bark does not change color or become depressed. Often a resin will appear on the bark in areas where a canker has formed.
During the winter, the Cytospora Canker causing fungus will live within an existing canker. Spores are formed within the cankered bark and when spring comes, they can be spread by weather, animals, insects, and people. The spores enter their new host through existing wounds.
IF LEFT UNTREATED:
If not treated for, Cytospora Canker will often kill its host tree. Even if a tree is not killed in the first season or two after infection however, the disease will cause tremendous aesthetic damage to the tree. This is due to the dying of branches, browning of needles, and the resin that forms from the cankers.
There is currently no viable treatment for Cytospora canker.