Orange pore fungus

The Orange pore fungus (lat. Pycnoporus coccineus) is a species of fungus in the Polyporaceae family. It is recognized by its vibrant orange-red fruit bodies and is primarily known as a white-rot pathogen that colonizes dead or stressed woody plant tissues.

The pathogen thrives by decomposing lignin and cellulose, which are structural components of wood. This process results in white rot, causing the internal structure of the wood to lose its integrity, becoming soft and fibrous. While it is primarily a decomposer, it can act as a wound parasite on various broadleaf tree species.

This fungus typically affects deciduous trees, including ornamental species and fruit trees. Development is accelerated in warm, humid conditions where moisture is trapped in tree hollows or bark fissures. It finds entry points through storm damage, pruning wounds, or areas weakened by other pathogens or environmental stress.

The most distinctive symptom of infection is the presence of bright, cinnabar-colored caps on the bark of infected trees or logs. Internally, the wood shows significant structural changes, appearing bleached and lightened. As the rot progresses, the tree loses mechanical strength, increasing the risk of structural failure.

Prevention and management require a proactive approach to maintain tree vitality and minimize fungal exposure:

• Perform regular pruning to remove dead or dying branches that serve as incubation sites.
• Seal all large pruning wounds with appropriate fungicides or wound dressings to block spore entry.
• Maintain tree health through proper irrigation and fertilization to boost natural defenses.
• Remove and destroy severely infected trees to reduce the overall spore load in the immediate area.