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Scientific name: Quassia amara
Family: Simarubaceae

Plant parts used

Wood and bark

Mode of action



Materials Methods of preparation How to use  Plant pests 
Quassia spray

4 tbsp of bark chips

1. Grind the bark chips.
Add powder to 2 liters
of boiling water.

2. Soak overnight bark chips
in 1-2 liters of cold water.

Spray on pests infected plants.

Colorado potato beetles' larvae
Several species of flies

Standard procedures for the preparation and application of the plant extracts

  1. Select plant parts that are free from diseases.
  2. When storing the plant parts for future usage, make sure that they are properly dried and are stored in an airy container (never use plastic container), away from direct sunlight and moisture. Make sure that they are free from molds before using them.
  3. Use utensils for the extract preparation that are not use for your food preparation and for drinking and cooking water containers. Clean properly all the utensils every time after using them.
  4. Do not have a direct contact with the crude extract while in the process of the preparation and during the application.
  5. Make sure that you place the plant extract out of reach of children and house pets while leaving it overnight.
  6. Harvest all the mature and ripe fruits before plant extract application.
  7. Always test the plant extract formulation on a few infested plants first before going into large scale spraying. When adding soap as an emulsifier, use a potash-based one.
  8. Wear protective clothing while applying the extract.
  9. Wash your hands after handling the plant extract.

Effect on humans

None; in fact, Quassia is used as hops substitute for making beer and has been long used as medicinal herb.

Effect on non-target organisms

None; it goes easy with bees and ladybugs.

External links


 to the top        PAN Germany, OISAT; Email oisat@pan-germany.org