Chlorosplenium

Chlorosplenium is a genus of fungi belonging to the Helotiales order, widely known for causing a striking green coloration in wood. In forest pathology and wood science, this organism is classified as a wood-staining fungus that can significantly alter the aesthetic and physical properties of the substrate it colonizes.

The primary agent is Chlorosplenium aeruginosum, a saprotrophic fungus that breaks down the structural components of wood. By secreting enzymes and pigments, the fungus penetrates the heartwood and sapwood, resulting in a permanent, vibrant green stain that is highly sought after by woodturners and artisans.

Symptoms of the infection include the presence of small, cup-shaped fruiting bodies, known as apothecia, which appear on the surface of rotting logs during damp seasons. As the mycelium spreads within the wood, the tissue becomes brittle, indicating that the fungus is actively decomposing the lignocellulosic matrix of the timber.

Conditions favorable for the spread of Chlorosplenium include high humidity, stagnant air, and the presence of dead or dying deciduous logs. It thrives in temperate forest environments where rainfall provides the necessary moisture for spore germination and mycelial growth on organic debris.

Control measures are primarily focused on preventative timber management rather than eradication. To prevent damage to stored lumber, it is essential to maintain low moisture levels, utilize proper stacking techniques with adequate airflow, and keep wood elevated from damp soil to discourage fungal colonization.