Small stagshorn

Small stagshorn (Calocera cornea) is a jelly fungus belonging to the Dacrymycetaceae family. In agronomic terms, it is recognized as a wood-decaying fungus that acts as a decomposer. While it primarily targets dead organic matter, its presence on living trees often indicates areas of severe stress, necrosis, or structural decay that require urgent attention from a gardener.

The fungus typically colonizes decaying deciduous wood, including stumps, fallen branches, and timber. However, it can also infect the dying or injured parts of garden trees and shrubs. By infiltrating the xylem through bark fissures or improper pruning cuts, the mycelium breaks down the wood tissue, which can weaken the structural integrity of the affected plant part over time.

Identifying this fungus is relatively straightforward due to its distinctive appearance. It produces clusters of bright yellow to orange, horn-shaped, or club-shaped fruiting bodies that emerge from the bark or wood surface. As the fungus consumes the lignin and cellulose, the wood becomes brittle, soft, and prone to breaking during windy conditions or under the weight of snow.

The development of Calocera cornea is highly dependent on environmental conditions, particularly humidity and temperature. It thrives in damp, shaded environments where air circulation is restricted. Spores are easily disseminated by wind and splashing water, allowing the fungus to quickly colonize any exposed wood surfaces or weak points in the garden's ecosystem.

Effective management focuses on preventive horticultural practices to keep trees healthy and limit fungal spread. Key strategies include:

• performing regular sanitary pruning to remove dead or diseased wood;
• applying fungicidal protective pastes to large pruning wounds or stem damage;
• improving air circulation within the canopy to reduce localized humidity;
• clearing away logs, stumps, and wood debris from the garden to minimize spore sources.