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How to Make Your Own Gnat or Fruit Fly Catcher

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Few creatures are more obnoxious to the human race than gnats and fruit flies. These two types of tiny flying insects are frequently confused for one another. While gnats are drawn to potted plants, fruit flies tend to prefer kitchens and garbage areas. Gnats may bite, but fruit flies don’t. Whether the bugs bite or not, the appearance of these tiny winged creatures in your home or office can be highly irritating. Although expensive elimination techniques are available, simple homemade methods can be just as effective.

Place the bait in the bottom of the jar. Use anything fruit flies are attracted to as bait; large quantities are not necessary. A piece of fruit, such as an apple core, or 1/2 cup of liquid is adequate.

Set the plastic bag in the jar with one corner pointed downward. The corner should hover approximately 1 inch above the bait. Wrap the top of the open bag over the lip of the jar and place a rubber band around the mouth of the jar to hold the bag in place.

Poke a tiny hole in the bottom of the corner of the bag. Make the hole very small — just large enough for flies to find their way in, but not big enough for them to be able to get back out.

Place the trap near the highest concentrations of flies.

Look through the glass to determine how many flies are caught in the trap. The trap can stay in use until full, but may become less effective with time.

Dispose of the entire trap without opening it to prevent flies from escaping.


If a plastic bag is not available, use a paper funnel or cover the jar with plastic wrap a poke one small hole in it. Add a drop of dish soap to liquid bait to break the surface tension. This removes the need for any funnel or covering, because it traps flies in the liquid and they drown. Create multiple traps to catch flies in multiple areas.


The trap will capture any adult insects, but effective elimination of flies and gnats requires elimination of all breeding areas as well.

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