Coral Spot is an incredibly common and widespread fungal disease that usually only attack dead or dying plant material. It can, however, infect healthy living tissues of woody plants by infecting dead material that is still attached and spreading down the plant. In healthy trees and trees, Coral Spot can cause dieback, although this symptom is uncommon in conifers. Another characteristic is the coral or red coloured pinhead-sized pustules that cover the infected material. Unlike many fungal diseases, the pustules can be present year-round, so material that is infected is very contagious because spores are released throughout most of the year.
Masses of tiny cushion-shaped coral pustules all over the branch. These can appear at any time of the year and will originate from a dead piece of woody material such as poor pruning cuts. May also produce similar dark red pustules in spring that on closer inspection look like raspberries but the size of pinheads.
Dead material left on the plant. Poor air circulation.
Multitude of pinhead sized pustules that can can be coral pink or deep red.
Dieback of branches.
Pruning diseased material at least 15cm past the visible symptoms and burning it. Complete uprooting and removal of diseased soft fruit shrubs which should then be burned. Using wound paint to seal up any plants which show particular susceptibility to the disease.
Once the diseased material has been removed, spray immediately and then twice more at 3-week intervals with an approved fungicide.
Coral spot has a complicated polycyclic life cycle that produces several types of infectious spores.
Not leaving piles of deadwood near trees. Making sure pruning cuts are clean and dry. Don't leave too much excess material on the plant.