Melanomma pulvis-pyrius

Melanomma pulvis-pyrius is a species of ascomycetous fungus belonging to the family Melanommataceae. It is widely recognized in mycology and plant pathology as a saprobic or weakly pathogenic fungus that colonizes the bark and dead wood of various broad-leaved trees and shrubs.

The host range of this fungus is extensive, covering many common deciduous trees such as oak, birch, willow, and maple. While it primarily acts as a decomposer of dead plant material, it can frequently be found on weakened trees, where it colonizes bark damaged by environmental stressors, such as frost cracks, sunscald, or insect infestations.

The most distinctive symptom of infection is the presence of numerous small, black, spherical fruiting bodies (perithecia) covering the bark surface. These clusters resemble dark dust or soot, which is characteristic of the species. As the fungus spreads, it can contribute to the degradation of the outer bark layers, leading to localized necrotic patches.

The fungus thrives in conditions of high humidity and moderate temperatures, which are optimal for spore production and dispersal via rain splashes or wind. The presence of existing wounds or fissures in the bark serves as the primary infection court, facilitating the entry of the fungus into the wood tissues.

Effective management and control are mainly focused on good horticultural practices:

• Removal of infected branches to reduce inoculum pressure.
• Prompt treatment of bark wounds to prevent colonization.
• Maintenance of tree vigor through proper irrigation and fertilization.
• Improving canopy airflow in dense plantings to reduce moisture accumulation.