Frosty funnel

The frosty funnel (lat. Clitocybe phyllophila) is primarily known as a saprotrophic fungus that decomposes leaf litter. However, in forest ecosystems and nurseries, it can act as a pathogen, invading the root systems of weakened trees and contributing to the development of white rot in the wood tissue.

This fungus typically affects a variety of broad-leaved and coniferous tree species. It thrives in environments where large accumulations of leaf litter and organic matter provide a constant nutrient base, allowing the mycelium to establish itself before potentially spreading to the roots of nearby woody plants.

Symptoms of infestation often include a gradual decline in tree vigor, chlorosis of the foliage, and the appearance of fruit bodies near the tree base. Internally, the roots and lower trunk exhibit signs of degradation, where the wood becomes soft, bleached, and loses its structural integrity due to the breakdown of lignin.

The development and spread of Clitocybe phyllophila are strongly correlated with high humidity levels and shaded, damp soil conditions. Spores are dispersed through wind and moisture, and their ability to infect is significantly increased by the presence of wounds or stress factors in the host plant's root system.

Effective management and prevention strategies include maintaining forest hygiene by removing excess debris and thinning overcrowded stands to improve air circulation.

• Sanitary pruning of infected trees.
• Monitoring soil moisture levels in nurseries.
• Application of fungicides to soil if outbreaks occur.