Why pheromones are used specifically in forests

Forest ecosystems are exposed over the long term to pressure from bark beetles and wood-boring insects, whose outbreaks can lead to extensive economic and ecological damage. Traditional chemical interventions are problematic in forest environments – both because of the need to protect non-target organisms and due to limited application options.

Pheromones represent a selective, non-toxic and environmentally acceptable tool that makes it possible to monitor and regulate pest populations without negatively affecting the surrounding environment.

What pheromones are and how they work

Pheromones are chemical signalling substances through which individuals of the same species communicate with one another. In forestry, the following are mainly used:

• aggregation pheromones – attract individuals to one place,
• sex pheromones – serve to attract mating partners,
• in some cases also anti-aggregation pheromones, which prevent tree colonization.

Insects are able to respond even to extremely low concentrations of these substances, enabling their effective use even over large areas.

Pheromone traps as a fundamental forest protection tool

The most widespread method of applying pheromones in forests is through pheromone traps. These consist of:

• a suitable mechanical trap (e.g. slot, cross-vane or tube trap),
• a pheromone dispenser with a specific active substance.

Traps are used mainly against bark beetles (e.g. Ips typographus, Ips duplicatus) and other bark beetles, whose aggregation pheromones have been well researched.

Areas of pheromone use in forestry

1. Monitoring pest populations

Pheromone traps make it possible to:

• monitor the start of swarming,
• evaluate the intensity of occurrence,
• make decisions on the timing of protective measures.

This is a key tool of integrated pest management.

2. Mass trapping

With a sufficient density of traps, pheromones can also be used to reduce the population density of the pest, especially in outbreak areas.

3. Protection of standing stands

In combination with suitable trap placement, it is possible to:

• divert bark beetles from healthy trees,

• concentrate their occurrence outside protected stands.

   

Advantages of pheromones over chemical interventions

The use of pheromones in forests brings several key advantages:

• high species selectivity,
• no residues in the environment,
• the possibility of long-term monitoring,

• compliance with the principles of sustainable forest management.

   

Limitations and proper use

Pheromones are not a universal solution. Their effectiveness depends on:

• correct identification of the target species,
• the appropriate trap type,
• placement and density of traps,
• timing with regard to the pest's biology.

Conclusion

Pheromones represent a modern, science-based forest protection tool that enables precise, environmentally friendly and effective management of forest pest populations. In combination with other measures, they form a solid foundation for an integrated approach to forest stand protection.