TECHNICAL REPORTS

The technique of mass trapping

A technique aimed at preventing damage to a crop by a pest by continuously reducing the population of that pest. To achieve this, traps with attractants specific to the pest to be controlled are used.

The traps are composed of:

  • The trap itself. It shall be designed for each type of insect.
  • The bait or attractant (usually food).
  • Retention agent — causes the death of the captured insect:
    • Same attractant in the case of liquids (death by drowning)
    • An insecticide in the case of dry attractants.

Why use mass trapping?

It is an effective technique that helps in the control of most pests. Mass trapping is more environmentally friendly than conventional phytosanitary treatments:

  • We do not apply insecticide directly to the fruit or plant to be consumed.
  • We do not kill beneficial insects, as the attractants are specific to the pest to be controlled.

How can the mass trapping technique be applied?

The traps are normally distributed evenly over the crop to be protected.

Sometimes, if the pest comes from neighbouring plots, you may reinforce the perimeters.

The number of traps, the orientation of the traps, their location within the tree, etc. will be determined by the manufacturer depending on the product, the crop and the pest to be controlled.

What trap dosage should be used?

It is important to follow the recommendations of the manufacturer and specialist technicians. Doses can vary greatly depending on the pest to be controlled, the sensitivity of the fruit or vegetable, the type of trap and attractant, the surface area of the orchard and the environmental conditions.

The number of traps used in the mass trapping technique will always be higher than the number of traps used to monitor the pest.

When is it placed and when is it removed?

Placement dates will be particular for each pest and crop; it is best to follow the manufacturer’s instructions and those of specialised technicians. However, the following points are important:

  • Anticipate the pest by taking into account the duration of the attractant. For example, if the attractant lasts for 6 months, the traps should be set 4-5 months before the approximate harvest date.
  • The traps shall not be removed until the duration of the attractant has elapsed, even if they have already been harvested. If necessary, the attractant should be replaced while the pest to be controlled is active.

Is this necessary if the mass trapping technique is being used?

The need to complement mass trapping with phytosanitary treatment will be determined by pest pressure, varietal sensitivity, climatology, geographical situation, etc.

It is important to carry out population monitoring or monitoring in parallel to mass trapping (this can be done with one of the same mass trapping traps) to determine if additional phytosanitary treatments are necessary.

It is fair to say that the use of mass trapping greatly facilitates pest control by reducing pest populations and, if additional phytosanitary treatment is required, makes it much more effective.