Laxitextum bicolor

Laxitextum bicolor is a basidiomycete fungus belonging to the Hericiaceae family, recognized primarily for its role in causing white rot in woody plants. It acts as a saprotroph that can transition into a facultative parasite, colonizing stressed or wounded trees. The fungal fruiting bodies are distinctive, typically appearing as effused-reflexed layers with a characteristic velvety texture, often found on the bark of decaying logs or living trees.

The fungus affects a variety of broad-leaved trees and occasionally fruit-bearing species. Infection typically initiates through entry points such as broken branches, frost cracks, or improper pruning cuts that leave heartwood exposed to the environment. Once inside, the mycelium breaks down lignin and cellulose, compromising the structural integrity of the wood and leading to the development of internal decay.

Symptoms of an infestation include the appearance of external brackets on the trunk, accompanied by a localized change in the wood's color and texture. Infected wood often becomes soft, fibrous, and pale in appearance. As the decay progresses, the overall health of the tree declines, characterized by canopy thinning, branch dieback, and an increased risk of structural failure during high winds.

The development of Laxitextum bicolor is favored by high humidity and moderate temperatures, which facilitate spore germination and mycelial spread. Spores are primarily dispersed via wind and rain, settling on wounded tissues where they can successfully colonize. Once established, the fungus can survive and spread throughout the heartwood for several years, gradually exhausting the host's vitality.

Management and prevention focus on maintaining tree health and minimizing potential entry points for the fungus.

• Sanitary pruning of dead or diseased limbs.
• Application of protective wound dressings on large cuts.
• Prompt removal and destruction of severely infected wood.
• Monitoring for early signs of fungal fruiting bodies.