2 Answers

I read the FAQ's for Earwigs and no mention was made of Earwig traps. I find they are the best and only way to kill Earwigs in my opinion. I once had a bed of mostly Marigolds and overnight it was desimated by baby Earwigs. I put out 1 of these traps in a baby food jar and the next morning it was full to the top with little gray baby Earwigs. It works for the adults too.

Making the traps 
In a small container--I like to use the scoops from laundry detergent-- mix equal parts of molasses or corn syrup, cooking oil, and full salt soy sauce. Bury it up to the brim where ever you have an Earwig problem. Prop a lid or stone or piece of wood over the top leaving a small hole for them to crawl into the container. You'll be surprised just how many you get.

The reason behind the ingredients 
The sweet molasses or corn syrup is the bait. 
The oil doesn't allow them to crawl out once they are in the container. 
The salt in the soy sauce kills them and the dark color makes it look like just the bottom of a hole. 
The original recipe called for molasses and that does make the concoction darker but I found corn syrup works just as good and it was what I had on hand the first time I tried this.

http://forums.gardenweb.com/forums/load/pests/msg0314444230969.html?6

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