When people see a large insect jumping among the crops and eating the leaves, the first thing that comes to mind is: "Have the locusts arrived?" The truth is that most of what we see in gardens and small farms is local grasshoppers that live alone and cause limited damage that can be easily controlled.
The desert locust (Schistocerca gregaria) is a completely different story: a migratory, cross-border pest that the Food and Agriculture Organization (FAO) describes as the most dangerous migratory pest in the world, and controlling it is the responsibility of official authorities, not the work of a farmer with a backpack sprayer. In this article we separate the two cases, and explain what you can actually do to protect your farm or garden in each one.
Pest: Locusts and grasshoppers are chewing insects that eat plant leaves and tips, and they can grow from small numbers into swarms.
Decision: Not every case needs control. The decision depends on density, the insect's stage, and the value of the threatened crop.
Timing: The young stages (nymphs) are easier to control than winged adults that can fly.
Common mistake: Spraying after the swarms have moved to another farm, so the pesticide is wasted with no result.
Rule: Monitor the field and its surroundings and estimate density before intervening, and cooperate with the competent authorities for large swarms.
Grasshopper and Locust: Close Relatives, but the Difference Is in Behavior
Locusts and grasshoppers belong to the order Orthoptera and the short-horned grasshopper family (Acrididae). The essential difference is not in appearance but in the locust's ability to change its phase:
- Solitary phase: In ordinary years the desert locust lives alone in the deserts, widely spaced, gray, brown, or green, and behaves like any ordinary grasshopper.
- Gregarious (swarming) phase: After good rains, numbers multiply in limited areas of green vegetation. The insects crowd together, and repeated contact between the hind legs triggers a behavioral and physical change: they are attracted to each other instead of repelled, the nymphs turn a striking yellow and black, and they move in crawling bands on the ground, then the adults become flying swarms. Sexually mature adults in the swarm turn a bright yellow.
Local grasshoppers in gardens do not turn into swarms this way, and their numbers stay tied to the season and the surrounding weeds.
The Numbers That Explain Why the Desert Locust Frightens the World
The danger of the desert locust does not come from a single locust but from the size of the swarm, the speed of its reproduction, and its ability to travel. These numbers show the picture:
- Swarm size: A single swarm can carry up to 80 million locusts per square kilometer.
- Appetite: A locust eats roughly its own weight in green plants each day, and a swarm covering one square kilometer eats in one day enough food for about 35,000 people.
- Flight distance: Swarms fly during the day with the wind and can cover up to 150 kilometers a day.
- Fast cycle: The female lays her eggs in moist sandy soil, they hatch after about two weeks, the nymphs become adults in about six weeks, and the adult needs at least a month to mature.
- Multiplication: If rains are available and no control takes place, numbers can multiply about 20 times in three months and 400 times in six months.
These numbers explain why locust control depends on early regional monitoring in the desert breeding areas before swarms form, and on specialized teams that use ultra-low-volume (ULV) spraying from the ground and the air, in addition to biopesticides based on the Metarhizium fungus and growth regulators applied to nymph bands.
If You See Desert Locusts or a Swarm: What to Do
Your role here is not control but quick reporting and protecting what you can. These steps are in order:
- Report immediately to the plant protection authority or the locust control center in your country, with the location, the approximate number, the color of the insects, and whether they are flying or crawling nymphs. Early reporting of nymph bands matters more than anything else, because controlling them before they fly is far easier.
- Do not try to control a swarm yourself with garden pesticides. The quantity needed and the area are far beyond the capacity of any farmer, and random spraying harms bees, livestock, and water sources without stopping the swarm.
- Protect what can be protected: seedlings and small vegetables can be temporarily covered with nets or row covers until the swarm passes.
- After the swarm passes: watch the moist sandy ground on your farm. If you notice many small holes in the soil, or small nymphs after two weeks, report to the competent authority again.
- Do not eat locusts collected from an area that was sprayed with pesticides, and do not feed them to poultry or livestock.
Grasshoppers in the Garden and Farm: Damage You Can Control
Local grasshoppers eat leaf edges, leaving irregular pieces, and may gnaw flowers, pods, and soft fruit. They prefer small seedlings and broadleaf plants such as lettuce, beans, and young corn, in addition to ornamental trees and young citrus. Common species in hot regions include:
- Egyptian grasshopper (Anacridium aegyptium): Large, up to 6 or 7 centimeters, gray-brown, with dark vertical stripes on its eyes, and it lives on trees and shrubs more than on the ground.
- Calotropis grasshopper (Poekilocerus bufonius): Colored blue, yellow, and green, it feeds mainly on the wild ushar plant (Calotropis), releases a foul-smelling liquid for defense, and may move to nearby crops.
- Cone-headed grasshoppers (Pyrgomorpha and others): Small, green or brown, common in gardens and lawns.
Most of these species lay their eggs in masses in the soil on unplowed land, field edges, and weedy areas. The nymphs hatch and start feeding on weeds, then move to the irrigated crop when the wild plants dry out. That is why many farmers notice that the attack starts from the side next to fallow land.
How Do You Know the Damage Is from a Grasshopper and Not a Caterpillar?
Caterpillars leave green or black granular droppings on the leaves and mostly eat at night, and you find them hiding in the soil or inside curled leaves. A grasshopper, on the other hand, you see during the day jumping when you approach, and its feeding cuts on the edges are wide and irregular. If the cut is at soil level and the seedling is severed at the stem, see our article on the cutworm.
The Control Plan in the Garden and Farm
Controlling local grasshoppers succeeds when you start early and from the source: the nymphs on the edges and weeds, then cultural measures, then spraying only when needed.
Target the Nymphs Before They Grow
This is the most important rule. Small nymphs cannot fly, they gather near hatching sites on the edges and in weeds, and they die more easily at lower rates.
The winged adult, however, flies and returns from neighboring land, and needs more spraying and more repetition. So check the farm edges and surrounding weeds at the start of the warm season, and if you see many small nymphs, this is the time to act.
Cultural Measures That Reduce Infestation
- Light tillage of neighboring land in the egg-laying season exposes the egg masses to the sun and birds.
- Managing surrounding weeds: Do not cut all the surrounding weeds suddenly in the middle of the season when you are unprepared, because that pushes the nymphs toward the crop. It is better to treat the edges with a pesticide first and then remove the weeds.
- Row covers and nets for seedlings and vegetables in small gardens, especially in the first weeks after planting.
- Birds and poultry: Chickens and wild birds are excellent grasshopper predators in small gardens and family farms.
Chemical Control for Edges and Clear Infestations
When numbers are large, we first spray the edges and surrounding weeds where the nymphs gather, then the crop itself if damage appears. Contact pesticides from the pyrethroid group (IRAC 3A) are the most used because they give fast knockdown, with care not to spray them on flowering plants because they are toxic to bees, and keeping them away from water sources.
The Products We Rely On for Grasshoppers
At Orkida Agri, for grasshoppers we rely on fast-knockdown contact pesticides with residual effect on the leaves, together with a sprayer suited to spraying edges and long stretches:
- Talstar 100 EC by FMC: bifenthrin 10%, a pyrethroid that works by contact and ingestion and has good residual effect on leaves. It is used on vegetables, wheat, alfalfa, trees, palms, and ornamentals. We use it to spray farm edges, surrounding weeds, and the infested crop, because nymphs arriving after spraying pick up the pesticide from the treated leaves.
- Warrior 10 CS by Syngenta: lambda-cyhalothrin in microcapsules that release the active ingredient gradually, so its effect on the plant lasts longer. Lambda-cyhalothrin is among the active ingredients used in locust and grasshopper control programs worldwide. We use it in open fields such as alfalfa, corn, wheat, and vegetables, and in rotation with Talstar when the season needs more than one spray.
- Eco Spray 20-Liter Electric Backpack Sprayer, Turbo Model: spraying edges, fences, and weeds takes a larger volume of solution and long walking, and the electric pump with a 20-liter tank keeps steady pressure and an even spray throughout the work, with an internal agitation system that prevents the pesticide from settling.
The best time to spray is early morning or before sunset, when grasshoppers are settled on the plant and less active, which FAO also recommends in locust control. Because leafy vegetables are picked quickly, follow the dose written on the label and the pre-harvest interval, and start with the edges and weeds before the crop itself.
Common Mistakes
Most control failures with grasshoppers come from the wrong timing or place, not from a weak pesticide:
- Spraying only when you see large adult grasshoppers: At that stage the damage has been done, and the adults fly and return. The nymphs are the target.
- Spraying the middle of the field and leaving the edges: The source is in the neighboring weeds, and the insects will return within days.
- Using household cockroach pesticides on vegetables: Public health pesticides are not registered on crops, and may leave unsafe residues.
- Confusing locust swarms with seasonal grasshoppers: A real swarm needs an official report, not a garden sprayer.
Frequently Asked Questions
Are the locust and the grasshopper the same insect?
They are from the same family, but the locust can switch from a solitary life to a group life in migratory swarms when crowded, while ordinary grasshoppers stay solitary. This switch is what makes the locust an agricultural disaster.
How do I know if what is on my farm is a desert locust?
The adult desert locust is about 6 to 8 centimeters long, and in swarms it is bright yellow when mature or pinkish-red when immature. Nymphs in the swarming phase are yellow with black markings and move in groups in one direction. If you see this picture, report to the plant protection authority immediately.
Do locusts attack houses and people?
They do not bite or transmit diseases to humans, and all their danger is to green plants, crops, and pastures. But dense swarms cause great annoyance and may enter open houses.
Can locusts be eaten?
Locusts are eaten in many cultures, but do not eat locusts collected from areas that may have been sprayed with pesticides, as they may carry harmful residues.
When do you spray grasshoppers in the garden?
When small nymphs appear in clear numbers at the start of the warm season, in the early morning or before sunset, starting with the edges and surrounding weeds. A few scattered grasshoppers in a large garden are not worth spraying, and it is enough to pick them by hand or let the birds do the job.
Is there biological control for locusts?
Yes, the best known are biopesticides based on the fungus Metarhizium acridum, which specifically infects locusts and grasshoppers, and official locust control programs use it, especially in environmentally sensitive areas. It is usually applied to nymph bands and takes days to show its effect.