Megacollybia platyphylla

Megacollybia platyphylla is a wood-inhabiting fungus that acts primarily as a saprotroph but can exhibit parasitic behavior when attacking weakened or stressed trees. Often found in woodland environments, this fungus plays a dual role in the ecosystem, contributing to the decomposition of dead wood while potentially compromising the structural integrity of living trees.

The fungus affects a variety of broad-leaved species such as oak, beech, and birch, as well as some coniferous trees in forest ecosystems. It typically enters through mechanical injuries, wounds on the root collar, or existing decay pockets, gradually spreading its mycelium through the woody tissue of the host plant.

Infected trees exhibit specific indicators, such as the appearance of characteristic mushrooms with broad gills near the tree base or on rotting roots. Internally, the fungus causes white rot, which degrades lignin and cellulose, turning the wood soft, fibrous, and pale. This deterioration weakens the tree, significantly increasing the risk of mechanical failure.

Development of this fungus is highly dependent on environmental factors, particularly high humidity and a constant supply of organic debris. The pathogen spreads via wind-dispersed spores and by vegetative contact between the mycelium of infected roots and healthy root systems, particularly in dense stands where tree roots are closely intertwined.

Control and prevention strategies focus on strict forest sanitation. To limit the spread of the disease, it is essential to remove decaying stumps, clear forest floors of woody debris, and minimize damage to the bark and root systems of healthy trees during thinning operations. Maintaining tree vigor through proper silvicultural practices is the best defense against fungal colonization.

• Systematic removal of infected logs and stumps.
• Prevention of physical damage to tree trunks and roots.
• Improving stand aeration to reduce excessive moisture.
• Regular inspections for signs of fungal fruiting bodies.