This is interesting to me because I have never heard of any weevils ever being in a worm farm bin. Rest assured though, I don't believe this poses any problem to your worm environment. Although, weevils do devastate the farming industry and is one of the gardeners arch enemies, they only eat plant life and stored grains. There are over 40,000 know species throughout the world but probably only one type of specie in your worm bin currently.
The weevil, with its long snout, will bore through the plant or grain making a hole only for the purpose of laying its eggs and will continue to do so for the rest of its adult life.
So, what to do about "Weevil Knievel"? Well, What I would do Stephen , is nothing. Just like fruit flies, soldier flies, or spider mites they pose no real threat to your worm farming system. Now, If you have an undesirable amount and they are competing with the worms for the food supply, then I would suggest two things.
Empty out all the contents of your worm bin and and throw everything away (except for the worms of course). Wash your worms thoroughly through some sort of strainer and start your worm bin all over again. It is paramount that you get rid of all the contents of your bin. You don't want them ending up in your bin again at some point. Burn the contents or throw them in the trash. Do not put it in your garden or lawn or the weevils will end up attacking your garden or some poor farmers crops or may end up in you worm bin again.
Next, you could find out what species you have and what it enjoys eating and stop feeding it that certain food, thus starving it. I'm not sure it works that way, but since they pose no threat to the worm farm it's worth trying. Usually every specie has a certain food they eat. So I've read, then you could let all of us know if it works. I know I would be interested.
Well Stephen, I hope that gives you a little criteria to go by. Keep us posted.
Happy Worm Farming,
Pauly (The worm Whisperer)
Feb 18, 2011 Rating
Use Diatomaceous Earth in the Worm Bin by: Pauly
I just wrote a few pages on Diatomaceous Earth and its benefits for worm farming and everything else. I had success in getting rid of some black gnats when I dusted the top inside of the worm bin as a DE study.
This should get rid of your weevils. It's safe, natural and non-toxic.