Eucalyptus Leaves Control Grain Moth

AgriculturePost-harvest activities


A Guatemalan farmer uses crushed eucalyptus leaves to control grain moths in stored maize.

José Elias is a farmer in Guatemala in Central America. For many years he had a problem with grain moths (Sitotroga cerealella) eating his stored maize. The moths would eat the centre of the kernels and leave the outside part. He didn’t know how to prevent this damage and sometimes he lost almost half of his corn harvest. One day, just by chance, he found a dried branch from a eucalyptus tree (Eucalyptus globulus) on the ground. He crushed it and smelled it – it almost made him choke. It made him think that if you exposed an insect or animal to that strong smell, the insect or animal would be forced away.

So, he decided to try storing his maize with some crushed eucalyptus leaves. He asked his family to help him collect and grind the leaves. It was a big job to crush them all by hand. He mixed the eucalyptus powder with his stored grain. After some experimenting José found that the strong-smelling eucalyptus leaves do protect stored maize from grain moths.

Here is his method. He picks the eucalyptus leaves, then dries them in the sun. When they are dry, he grinds them to a powder. He places a layer of the eucalyptus leaf powder, about one centimetre high, on the ground where he plans to store the maize. On top he puts a layer of maize cobs, about 15 centimetres high. Then he puts another layer of eucalyptus powder on top of the maize. He continues to alternate one layer of maize cobs (15 centimetres deep) with a layer of eucalyptus powder (one centimetre deep) until all the maize is stored.

Now moths don’t eat his stored corn. The powder repels them by its smell. This method has been a great success for José Elias. Not only has he found a way to protect his maize from moths, but this success has also encouraged him to continue experimenting to find other ways to control pests using local plants.

Pesticide Safety Rules

  1. Store pesticides in original containers, never in food or drink containers. Store in a safe place, out of reach of children and animals. Keep away from food, water, and animal feeds.
  2. Follow the instructions and safety guidelines on the container. Obey the precautions. Use the amount instructed, in the correct manner. Know beforehand what to do in case of an accident.
  3. Don’t spray on a windy day. Never spray into the wind.
  4. Don’t let pesticides get on your skin. Wear protective clothing (cover all of your skin, if possible—including your feet, hands and head). Be especially careful when working with pesticide concentrates.
  5. If pesticide gets on skin, wash immediately. Get medical help if necessary. If it gets on clothes, remove clothes and wash the clothes before wearing them again. Always wash after using pesticides, even if you think none touched you.
  6. Don’t let pesticides get in your eyes. If possible, wear goggles or glasses.
  7. Avoid breathing pesticides in. (If possible, wear a mask, respirator, etc.)
  8. Don’t eat, drink or smoke near pesticides. Wash your hands and face with soap and water before eating, drinking or smoking.
  9. Wash all equipment used and store in a clean place.
  10. Don’t contaminate water (in rivers, wells, ponds, etc.) with pesticides.
  11. Don’t reuse empty pesticide containers. Rinse them at least twice, crush them and bury them.
  12. Keep people and animals out of recently sprayed areas.
  13. Don’t eat or sell food crops that have recently been sprayed.


  • This script is based on an interview with José Elias Socop Menchu, of the Department of Totonicapan, Guatemala.