The phytosanitary protection of the forest is of particular importance in Morocco because of the vital role both ecological and socio-economic that this heritage plays. However, the forest is dependent on attacks by defoliating insects that harm it by predisposing it to other so-called secondary pests that complete its degradation and affect the multiple functions it is called to perform. Each time the defoliant insect population level exceeds the tolerable threshold, the damage to the forest can be catastrophic.
The Plant Protection Service intervenes by aerial and terrestrial treatments to limit the depredations mainly due to the processionary of pine and lymantria and also to avoid the nuisances caused especially by the processionary caterpillar of pine on human health (dermatitis, etc.) and livestock. The control decision is made based on a monitoring strategy based on pest population levels.
The actions carried out for the phytosanitary protection of the forest consist in:
- Monitor the health of the forest and draw up the maps of infestations (action carried out by the agents of the High Commission for Water and Forest);
- Organise campaigns to combat the main forest pests in the different forest regions;
- Check the effectiveness of treatments.
For other defoliating insects, localized treatments are performed when there is a high attack to avoid the installation of outbreaks. These are the Oak Leafroller, the Orgy, the Catocales, the Cedar Processionary, the Cedar Leafroller, etc.
The campaigns of struggle take place in spring for the Bombyx and the other defoliants of the oaks and between July and December for the Processionnaire du pin.