Locusts: how they develop and when to fight them

Why locusts are dangerous

Locusts damage grain, melon and vegetable crops, pastures and hayfields. An adult locust can eat roughly its own weight in food per day. Swarming species gather into hopper bands and swarms and travel long distances, so a hotspot on neighbouring land is a threat to your crops too.

The most dangerous species

• Italian locust — a non-swarming species, but at high numbers it severely damages crops and pastures.
• Moroccan locust — a swarming species that damages pastures and crops.
• Migratory locust — a swarming species associated with reed beds near water.

How locusts develop

1. Eggs in pods. In summer and autumn females lay eggs in the soil, in egg pods. The eggs overwinter.
2. Hoppers. In spring wingless hoppers emerge and go through several instars. They cannot fly yet and stay in hotspots.
3. Adults. Once winged, locusts start to fly, and swarming species form swarms.

Why treatment targets hoppers

Hoppers are concentrated in a limited area and cannot fly away. Treating young hoppers takes less product and works better than fighting swarms of adults. That is why it is important to survey fields on time and not miss the window.

Control methods

• Survey — counting egg pods, then monitoring hatching and hopper density.
• Ground spraying — a vehicle-mounted sprayer for large areas, backpack sprayers for edges and hard-to-reach spots.
• Barrier strips — treating strips across the hoppers’ path towards crops.
• Checking effectiveness — verifying the result and repeating treatment if needed.

Safety

• We give advance notice of treatment dates.
• We take apiaries, water and grazing livestock into account when choosing the product and timing.
• We use approved pesticides according to the regulations.