Control of Thaumetopoea pityocampa

The problems that are caused almost every year in many peri-urban and aesthetic forests and pine groves by pine processionary caterpillar are widely known. The main problem concerns their defoliant action since they are feeding exclusively and particularly greedily by the needles of coniferous trees which affect and can even reach to the total disaster of foliage and consequently to tree desiccation. Furthermore, they create the conditions for secondary damages by other insects but also significant loss of biomass of the trees (20%-45%) and all of these by one generation per year.
 
The insect control methods are disaggregated into biological, mechanical and chemical methods. Chemical methods include the use of chemical formulations (at recent years growth hormone inhibitors are used) and it is better to be implemented by ULV (Ultra Low-Volume) sprayings devices. Mechanical methods are applied in those cases that the infestation is limited and is detected in short threes. In that case, the final nests may be cut down and then burnt. During biological control of caterpillar (methods applied by Ecodevelopment S.A.), they are carried out ground spraying applications with the use of biological formulation and in particular, at the moment, of the formulation Bacillus thuringiensis sub. Kurstaki (formulation for stomach infestation).
 
For the application of a pine caterpillar control project it is necessary to be done accurate determination of the area of intervention through the mapping of all affected trees, array of trees, bocages etc, the imaging of trees’ distribution in cartographic backgrounds, the determination of the area of separate arrays of trees, the mapping of various natural obstacles for spraying implementations. Before any other intervention, it is carried out systematic monitoring of evolution of the infestation of pine trees from the stage of eggs to the first hatchings of larvae and the area for intervention are strictly delineated. Spaying is applied by the use of biological formulation and more specific of the formulation Bacillus thuringiensis sub. Kurstaki (formulation for stomach infestation). These interventions aim at the decline of caterpillar population in affected trees with the minimum environmental and also financial cost. Spraying interventions within the boundaries of a municipality are usually completed in 4-5 days and spraying efficiency check is carried out between two weeks later.