How to Make a Killing Jar:

[General Guidelines] [Materials Needed] [Construction of Killing Jar] [Use and Care]

• A killing jar can be made from a wide-mouth glass jar with a metal screw-on lid. You can make killing jars out of different types of jars. Peanut butter jars (18 oz.) and olive jars (8 oz.) are good choices.

• Ethyl acetate is the recommended insect killing agent for most collectors for several reasons. Its fumes are less toxic to humans than other substances, and insects placed in a jar with ethyl acetate are knocked out quickly and remain limp as long as they are kept in the jar. Ethyl acetate can be ordered from biological supply houses, and jars can be recharged easily by adding more ethyl acetate. Some collectors dislike ethyl acetate because it kills the insects too slowly, and insects that appear dead sometimes revive when they are removed from the jar. Beginners who cannot obtain ethyl acetate can substitute nail polish remover.

• ethyl acetate
• eye dropper
• plaster of Paris
• tissue (facial tissue, paper towel, other absorbent paper)
• wide-mouth glass jar with screw lid

1. Make sure the jar is clean and dry.

2. Pour about 1 inch of wet plaster of Paris into the jar. Plaster of Paris is used to absorb ethyl acetate.

3. Allow time to set.

4. Add ethyl acetate to the jar with an eye dropper until the plaster of Paris appears saturated. No pools of ethyl acetate should remain on the surface.

5. Place several crumpled pieces of tissue paper into the jar to keep the insect from getting damaged and to absorb moisture.

6. Label the jar with the word "poison."

7. For safety, wrap the bottom of the jar with masking tape or other suitable tape to absorb shocks and prevent the jar from breaking.

1. When transferring insects from a collecting device to the killing jar or collecting them directly into the jar, keep the jar closed whenever possible.

2. Keep small, delicate insects in a jar by themselves. Insects such as large beetles are apt to mutilate small flies and other delicate specimens if kept in the same jar.

3. Keep a special jar for moths and butterflies. When these die, they shed large quantities of scales that stick to other insects.

4. Keep the inside of the jar dry. Wipe out wet jars with paper or cloth. To reduce condensation, keep the jar out of the sun and change the absorbent paper frequently. Do not crowd the jar with large juicy insects such as grasshoppers.

5. Empty the insects from the jar before they become entangled in a ball at the bottom. This will prevent damage to the smaller specimens and reduce discoloration caused by moisture buildup.

6. Recharge jars before each field trip by adding ethyl acetate with an eye dropper.

7. Keep jars away from young children and pets.