FAQ Locust

How can locusts be controlled?

At present the primary method of controlling Desert Locust swarms and hopper bands is with mainly organophosphate chemicals applied in small concentrated doses (referred to as ultra low volume (ULV) formulation) by vehicle-mounted and aerial sprayers and to a lesser extent by knapsack and hand-held sprayers.

How can small patches of locusts be sprayed using (Ultra Low Volume) ULV equipment?

Spraying small targets with ULV spraying can be wasteful. The most appropriate type of sprayer should be used, i.e. handheld sprayers for very small targets. If the patches are still smaller than a swarm width, then a double pass can be made at a short distance upwind of them

Explain different control measures of locusts?

Mechanical methods – digging trenches, beating and burning
Baiting – scattering locust food impregnated with insecticide
Dusting – applying a fine dust impregnated with insecticide
Spraying liquid insecticides.

The locusts are still alive after spraying – what are the possible causes of Control failure?

It is tempting to blame the insecticide if control is poor, when in fact it is more likely to be caused by application problems. Failure can be caused by many factors including droplets too large or too small, wind too strong or too weak, strong convection, spray emission too high, under dosing, locusts sheltered by vegetation and locusts moving before the spray reaches them. Only when these factors have been eliminated should the pesticide be suspected and sent for testing for active ingredient content.

Who carries out locust control operations?

Locust survey and control are primarily responsibility of the “Ministry of Agriculture, Co-operation & Farmers Welfare” in locust affected States and are operations undertaken by Locust Warning organisation (LWO). There are also several Locust Circle Offices (LCO’S) that assist with survey and control operations. During times of outbreaks and plagues, external assistance from the donor community and other international organizations is usually required.

What is the spray target? Whether locusts or the vegetation?

For most spraying, both are the target since the locust gets some of its dose from direct contact, and some from indirect contact and stomach action – rubbing against and feeding on the sprayed vegetation.

What are the important factors to be considered while ULV Spraying?

  • Droplet size (depends on the atomizer)
  • Droplet spectrum (depends on the atomizer)
  • Work rate (depends on the sprayer platform and flow rate)
  • Operator safety (depends on various design features)
  • Ease of use (depends on various design features)
  • Reliability (depends on construction materials and design.

If there are no aircraft sprayers available, how can locusts in tall trees be sprayed using ground- based sprayers?

Most ground sprayers, even motorized air blast sprayers, cannot reach swarms in tall trees and attempts at control can be very wasteful of pesticide and dangerous for operators standing underneath the spray cloud. However, a version is available with an extended mast that can be used in trees up to around 10 m height This cannot easily be used on the move since the mast would break over rough ground, so should be used in short blasts at different locations upwind of the swarm. The concept of dosage does not really apply, and the process is likely to be wasteful, but may be effective.

What are the other agencies/ministries involved in the locust control apart from agriculture ministry?

Apart from the Ministry of Agriculture and Farmers Welfare, Department of Agriculture, Cooperation and Farmers Welfare, other ministries (External Affairs, Home Affairs, Defence, Earth Sciences, Civil Aviation and Communications)and stakeholders (e.g. State Governments, Health Department, farmers) are to be involved during a Desert Locust emergency. The role and responsibilities of these stakeholders is defined in the implementation part of the plan.