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Script 32.2

Script

Those of you who are troubled by locusts and grasshoppers on your farms should know that there are many methods of locust and grasshopper control that are cheaper and safer than chemical pesticides. Experiment with a combination of techniques to find out which work best on your farm.

Both locusts and grasshoppers can damage crops. When grasshoppers move into your fields, they usually stay, eating a lot of your crops every year. Locusts look the same as grasshoppers and sometimes act the same too. However, at other times, locusts get together in large groups called “swarms”. Then they travel long distances, eating everything in their path. When locusts swarm, it is almost impossible for individual farmers to control them. Often, they need help from the government or other organizations.

Here’s the good news. There are simple techniques you can use to control grasshoppers and non swarming locusts. Remember, when locusts aren’t in a large swarm, they act like grasshoppers, so you use the same techniques to control them that you use for grasshoppers.

Digging up eggs

Here is a simple way to reduce grasshoppers in your fields. With just a hoe, you can reduce the number of grasshoppers by eighty to ninety per cent.

Start by observing when and where the female locusts and grasshoppers lay their eggs. You will know they are laying their eggs when you see them pushing their bodies into the ground. Grasshoppers and locusts lay their eggs in pods. That is, they lay about 50 eggs in a hole 5 centimetres below the ground, and cover them with a foam that looks like a sponge you use for washing.

When you find the eggs, mark the spots so that you can find them again. Then, when you go back, all you need to do is dig up the eggs from the different spots. If there are too many egg pods to dig up with just a hoe, you can use a plow to bring the eggs to the surface. However, plowing also makes your soil more vulnerable to erosion, so only do this when you really need to.

Spread the eggs out on the ground so that they are exposed to the air. That way, the eggs will dry up or birds will come and have a feast! It’s best to do this on a hot, dry day so the eggs dry up quickly. Or, feed the grasshopper and locust eggs to your poultry. Make sure that your neighbours know about this technique too! Otherwise, the grasshoppers will just move back into your fields from your neighbours’ fields.

Poultry eat locusts and grasshoppers

Locusts and grasshoppers make a tasty meal for ducks, guinea fowl and chickens! So keep ducks, guinea fowl and chickens on your farm to reduce the number of grasshoppers and locusts. If you don’t have poultry, maybe you can borrow some from your neighbour.

The more ducks and chickens you have on your farm, the more grasshoppers and locusts they will eat. So, try this idea. Gather all the poultry in your community in one field. After, they have eaten the grasshoppers and locusts there, put them in the next field. And so on. Keep doing this until the poultry have been in each field. This way, each field will have fewer locusts and grasshoppers because of hungry poultry. In China, they have used groups of more than 70,000 ducks and chickens to help control locust invasions.

The great thing is that guinea fowl, chickens and ducks also eat other pests. Fat poultry, fewer grasshoppers, locusts and other pests, what else can a farmer ask for!

Choose your plant friends!

Sometimes you can distract grasshoppers and locusts from eating your crops by growing different plants around the edge of your fields. For example, plant marigolds. Grasshoppers like to eat marigolds so they leave your crops alone. Also, when the grasshoppers are eating the marigolds, you can spray them with an insecticide, preferably a natural one. Marigolds also repel other insect pests, including nematodes and whiteflies.

Grasshoppers are also repelled by some crops too, so you can plant a crop around your fields which the grasshoppers don’t like. For example, grasshoppers don’t like sorghum as much as maize and millet. So, plant sorghum around your fields of millet and maize to discourage grasshoppers and locusts from entering your fields.

Trees and shrubs

Planting trees and shrubs may also discourage grasshoppers and locusts from laying eggs. In China and Cyprus, they have planted trees and shrubs to help manage their locust and grasshopper problems. They planted them on the borders of their fields, on the shores of rivers and lakes, on barren lands, old river beds, sandy lands or dunes, flood plains and other places where locusts breed. Besides discouraging locusts from staying and laying their eggs, these trees, shrubs and flowering plants shelter birds, parasitic wasps and other natural enemies of locusts and grasshoppers. So plant trees, shrubs, and flowering plants to discourage grasshoppers and locusts and encourage their natural enemies.

Grasshoppers and locusts like areas with some vegetation but not too much. Having a permanent cover on the soil discourages grasshoppers and locusts from laying eggs. It also makes it harder for the hatched locusts to emerge from the soil.

If you can’t plant trees, try the opposite strategy. Grasshoppers also do not like bare ground. In the Sahel, farmers leave a strip of bare ground, about 2 to 3 metres wide, around their fields to discourage grasshoppers from coming into their fields. So, if you can’t grow some good permanent cover around your fields, try the opposite. Farmers in the Sahel also keep their fields clean of weeds to control locusts. Remember that bare ground is vulnerable to soil erosion, so be careful.

Traps

Spread out some food, such as bran, that grasshoppers and locusts like to eat and spray that food with neem or another natural insecticide. When the locusts or grasshoppers eat the food, they are poisoned. You can make the trap even more attractive by adding a little molasses to the food.

For a small field or garden, make a trap with a bucket or jar. Fill the jar or bucket half full with water and add a little molasses or something else sweet. Or use a bucket with a light over it. Place a few of these buckets wherever you find the most grasshoppers or locusts. The grasshoppers are attracted by the bait or light and fall into the bucket or jar. These traps can be made more effective by pouring a thin film of kerosene on top of the water. The kerosene prevents the insects from escaping. However, if you use kerosene, don’t feed the insects to your poultry!

You can also use piles of straw as traps. Grasshoppers often move to the edge of the field at night and will shelter in the straw because it is warmer. Knowing where they are that night, you can easily spray them with a natural insecticide. You can also burn the straw, although this way you won’t have the straw for the next night.

In case of invasion

If a swarm of locusts is heading your way, there is not much you can do by yourself. Here’s one technique that your community can use in cases where immature locusts travel together in marching bands. Use barriers to direct locusts into pits. The trick is to guess where the locusts are going and then to put the barriers and trenches in their path. The barriers should be 33 to 45 cm high and can be made of fabric, wood or other materials. Place the barriers so that the locusts are directed towards the pits. The pits should be at least 40 cm deep, 1 metre wide and have vertical walls. When there are many locusts in the pits, you can burn them or bury them. During years when there are lots of grasshoppers, you can plant crops that locusts and grasshoppers don’t like such as: potatoes, sweet potatoes, rice, peanuts, beans, cotton, sesame, and green manure crops.

Locusts and grasshoppers as food

People in Africa, South America and other areas eat locusts and grasshoppers as food. For example, some Mauritanian pastoralists kill locusts for both food and medicine. They grind them into a powder to eat. They believe that since locusts eat all trees, they must be the cure for all diseases, since there is a tree to cure every sickness.

Warning!

Unfortunately, people wishing to eat locusts and grasshoppers or use them as animal feed have to be careful these days. If the locusts or grasshoppers have been sprayed with chemicals, they can harm you and your animals. For locusts, you should ask your local extension officer if the locusts have been sprayed either in your country or in other countries. Remember, locusts travel large distances very quickly.

For grasshoppers, you can probably ask your neighbours and nearby communities. If they do spray, tell them about some of the methods mentioned here and suggest they try them. Then, later, all of you will have a valuable source of food.

Conclusion

Integrated pest management of locusts, grasshoppers and other pests requires thought, observation, and experimentation. However, there are many advantages.

  1. Many of these techniques will help control other crop pests. As you learn what works best to protect your crops, you will be developing a system that will work against all your pests. The best part is that your integrated pest management system will last for a long time. You can tell your children about it and they will tell their children and so on.
  2. Using fewer chemicals means healthier soil with more helpful insects and less money spent on harmful chemicals.
  3. When free of pesticides, locusts and grasshoppers are good food for your chickens or yourselves.

Acknowledgements

  • This script was researched and written by Boyd Fuller, M.Sc. (Agricultural Engineering), Toronto, Canada.
  • Thank you to the following advisors for reviewing this script:
    • Dr. George Popov, Department of Entomology, Natural History Museum, London, U.K.
    • Dr. Helene Chiasson, Entomologist, Montreal, Canada.
    • Dr. Peter Kevan, Department of Environmental Biology, University of Guelph, Guelph, Canada.
  • In August 1992, we asked our participants what insect pests were the biggest problems for local farmers. Grasshoppers and locusts were two of the insects that many farmers had problems with.

Information Sources

  • Grasshoppers & Locusts: The plague of the Sahel (1993, 114 pages) by the Panos Institute, published by Panos Publications Ltd., 9 White Lion Street, London, N1 9PD, UK.
  • Locusts and Grasshoppers: a handbook for their study and control (1928, 352 pages) by B.J. Uvarov, published by the Imperial Bureau of Entomology, London, United Kingdom.
  • “Environmentally Sound Locust Management in China” (July 1991, 9 pages) in The IPM Practitioner, vol. 13, no. 7, by Anghe Zhang, William Quarles and William Olkowski, published by the Bio Integral Resource Centre (BIRC), PO Box 7414, Berkeley CA, U.S.A. 94707.
  • “Agroforestry and IPM in China” (April, 1992, 12 pages) in The IPM Practitioner, vol. 14, no. 4, by Anghe Zhang, William Olkowski, published by the Bio Integral Resource Centre (BIRC), PO Box 7414, Berkeley CA, U.S.A. 94707.
  • Conference Notes from “Entomological Society of America’s 1992 Annual Meeting: Part VIII” (October, 1993, 3 pages) in The IPM Practitioner, vol 15, no. 10, published by the Bio Integral Resource Centre (BIRC), PO Box 7414, Berkeley CA, U.S.A. 94707.
  • Locust Handbook, (1990, 204 pages) edited by A. Steedman, published by Natural Resources Institute, Overseas Development Administration, U.K.
  • Neem: a natural insecticide (34 pages) published by “Gewinnung natüralicher Insektizide aus tropischen Pflanzen”, Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ German Agency for Technical Cooperation), Postfach 5180, 6236 Eschborn 1, Germany.
  • “Grasshoppers as Chicken Feed: an idea that may work.” (1987, 1 page) in Senelaa: the Gambian Fieldworkers’ Magazine (no. 45) by Sankung B. Sagnia, published by the Extension Aids Unit of the Ministry of Agriculture, Yundum, Gambia.
  • Agricultural Pests of India and South East Asia (1976) by Avtar Singh Atwaal, published in Dehli and Ludhiana, India.
  • “Controlling Grasshoppers” in The Farming World. Interviews with Bill Page of the Tropical Development Research Institute (no. 1273) and Dr. Wester Modder of the University of Ibadan, Nigeria (no. 1291). Anti Locust Research Centre, College House, Wrights Lane, London W85 S5, UK