Processionary caterpillars, often seen in temperate regions, pose a serious threat to the health of trees and humans. These insects, recognizable by their movement in single file, are particularly dangerous because of their stinging hairs. This guide aims to provide effective and environmentally friendly methods to prevent their appearance and proliferation.
General preventive methods against processionary caterpillars
In order to effectively protect your green space, it is essential to adopt preventative practices well before these pests become visible. Among the most effective measures, installing pheromone traps in early spring can significantly reduce the population of moths that lay the eggs that cause caterpillars. Another preventive measure involves the use of physical barriers around tree trunks to prevent caterpillars from climbing them and forming nests.
Use of natural predators
The introduction of natural predators constitutes an ecological strategy to control the processionary caterpillar population. THE birds, such as tits, are avid consumers of these caterpillars and can therefore help regulate their numbers. Likewise, certain species of parasitoid wasps specifically attack the larvae and eggs of caterpillars, thus limiting their reproduction. Encouraging biodiversity in your garden by installing nest boxes and fostering a rich ecosystem can significantly help this cause.
Ecological control techniques
The use of biological control via the Thuringian bacillus (Bt) is also a very effective method for the management of processionary caterpillars. This bacteria, when applied in the form of a spray to infested trees, is ingested by the caterpillars which are then exterminated. It is crucial to apply this treatment at the right time, ideally when the caterpillars start feeding, for the product to be most effective.
Mechanical intervention to remove nests
Manual removal of nests is a direct technique to reduce the proliferation of caterpillars. This operation, consisting of removing the nests using specific tools, often in autumn or winter when the caterpillars are inactive, must be carried out by professionals equipped with suitable protection to avoid any contact with the stinging hairs of the caterpillars.
In short, controlling processionary caterpillars requires an integrated approach including preventive practices, the use of natural predators, biological control methods, and mechanical interventions. Each of these techniques contributes to a healthier environment and the protection of local biodiversity.
