Dacrymycetes

Dacrymycetes are a class of basidiomycete fungi primarily recognized for their role as wood-decay agents. While they serve a vital function in nutrient cycling in natural ecosystems by breaking down complex polymers, they pose significant risks in forestry by causing brown rot, which compromises the structural integrity of timber.

The pathogens typically involved in wood decay belong to this class, with the genus Dacrymyces being the most prominent. They specifically target softwoods, decomposing cellulose and hemicellulose. This process leaves behind a weakened, brittle wood residue that is highly susceptible to mechanical failure and further biological attacks.

Infestation is easily identified by the presence of gelatinous, bright-colored fruiting bodies on the surface of bark or decaying wood. These structures, ranging from yellow to deep orange, are highly responsive to moisture levels. They shrink and become dormant during dry periods but swell to release spores during wet, humid weather.

The development of these fungi is favored by high moisture content in wood and moderate temperatures. They often establish themselves in trees that have been previously weakened by environmental stressors, frost, or insect infestations, as the reduced vitality of the tree prevents efficient defense against fungal colonization.

Control and prevention strategies focus on maintaining forest hygiene and reducing environmental stressors. Key actions include:

• conducting timely sanitary logging to remove decaying wood;
• avoiding mechanical damage to the bark of healthy trees;
• improving air circulation within stands to prevent sustained surface moisture.