Stag beetle

Systematic position: The stag beetle (Lucanus cervus) is a member of the order Coleoptera and the family Lucanidae. Recognized for the males' massive, antler-like mandibles, this insect is a protected species in many parts of the world, serving as a bioindicator of healthy forest ecosystems.

Crops affected: The larvae of the stag beetle are saproxylic, meaning they feed on decaying wood. While they primarily target oak and beech logs, they can occasionally be found in old or decaying fruit trees such as apple, pear, and plum, especially if these trees are already in a state of advanced decline.

Biology and life cycle: The lifecycle of the stag beetle is notably long, lasting between four and six years. The vast majority of this time is spent in the larval stage underground or within rotting timber. After passing through several instars, the larvae pupate in a specialized chamber and emerge as adults during the early summer months.

Nature of damage and economic impact: Stag beetles are generally not considered primary agricultural pests. They do not attack healthy wood; rather, they colonize trees that are already dead or dying. In an orchard setting, their presence is usually a symptom of existing wood rot, though their activity can accelerate the structural breakdown of older, compromised trees.

Protection measures: Because Lucanus cervus is protected under various conservation legislations, chemical control is not recommended. Instead, integrate the following strategies to manage wood rot:

• Regular removal of decaying stumps and dead wood from the orchard.
• Sanitary pruning of infected or rotting branches.
• Maintaining healthy tree vigor to prevent the conditions that larvae prefer.