Golden canker is a fungal disease which attacks Pagoda dogwood, or Cornus alternifolia. The disease does not affect other types of dogwood. Golden canker is found in the eastern half of the United States and Canada. Telltale evidence of a canker infection are shoots and branches that range from a tan colour through to a golden yellow colour. The areas of infection stand out against the healthy branches, which remain a typical reddish brown colour. Infected branches wilt and die.
Golden canker can be seen more easily in the spring and fall when leaves are not present. Close examination will reveal orange dots along the branches in the canker areas; these are the fungal spores. Fungal spores are spread by rain and wind to other parts of the tree. Infected trees can survive for many years but, once the canker invades the main trunk, the tree will succumb.
The only effective treatment for golden canker is to cut out infected branches and twigs. This pruning should be done when the tree is dormant and when temperatures are consistently below freezing. Cuts should be made two buds below the infected branch and, if possible, avoid cutting into the main trunk. Pruners or loppers must be sterilized after each cut with a 10% bleach solution or with Lysol. Infected branches should be taken away and not put into a compost pile. They should be either burned or buried.
Submitted by Elizabeth Spedaliere