Lachnum corticale

The most visible indicator of infection is the presence of small, white, fuzzy cup-shaped fungi appearing in clusters on the tree's bark.

Infected bark areas often show signs of necrosis, including darkening, cracking, and eventual peeling away from the underlying wood.

As the infection progresses, branches may display signs of dieback, with leaves wilting and failing prematurely due to nutrient transport disruption.

The affected wood may become brittle and dry, providing a clear visual contrast to healthy sections of the trunk or limbs.

Initial infection often occurs in hidden areas of the tree, making it necessary to inspect lower branches and shaded parts of the bark regularly.

The fungus Lachnum corticale (syn. Dasyscyphus corticalis) is an ascomycete species that often colonizes the bark of weakened trees.

It exists as a saprotrophic organism that can become an opportunistic pathogen when a host plant's resistance is compromised.

The fungus produces distinctive, tiny, cup-shaped apothecia covered with fine, white, hair-like structures, making it identifiable under close inspection.

It spreads through the production of numerous spores, which are disseminated by wind, rainwater, and physical contact within the canopy.

The mycelium effectively colonizes the outer bark layers, gradually absorbing nutrients from the dying tissue of the host plant.

High humidity and extended periods of damp weather are the primary environmental conditions that trigger the growth of Lachnum corticale.

Trees stressed by drought, poor soil nutrition, or physical damage to the trunk are significantly more susceptible to colonization by this fungus.

Poor airflow within the tree canopy, often caused by lack of pruning, creates a stagnant environment favorable for spore germination.

Old, neglected orchards or forests with significant quantities of deadwood serve as primary reservoirs for this fungal pathogen.

The fungus tends to thrive in temperate climates, showing peak activity during the spring and autumn seasons when temperatures are moderate.

While often considered secondary, the fungus contributes to the decline of trees already struggling with other environmental or biological stressors.

It causes localized tissue death in the bark, which can eventually lead to the girdling of smaller branches if the infection is widespread.

The physical damage to the bark layers interferes with the tree's ability to maintain hydration and distribute nutrients effectively.

Persistent infestations weaken the structural integrity of branches, making them more prone to breakage during storms or heavy winds.

By degrading the bark, the fungus creates entry points for more aggressive pathogens and wood-boring insects, further endangering the tree.

Sanitary pruning is the most effective way to manage the disease, ensuring all infected or dead branches are removed promptly.

It is crucial to dispose of removed infected material away from the orchard to prevent further spore dissemination.

Applying antiseptic wound sealants to cuts can help prevent the ingress of new fungal spores into fresh exposed wood.

Maintaining overall tree vigor through adequate watering and balanced fertilization remains the best long-term defensive strategy.

If the infection is severe, the application of copper-based fungicides during the dormant season can help reduce the spore load in the immediate environment.