Before I could realize it they had eaten and nested inside my immature corn cobs and ruined almost all of them. Is there any way to fight them back? Diatomacious Earth? Organic mulch seems to provide a haven for these things.
Are you sure it was earwigs and not the European Corn Borer?
Earwigs can be controlled with garlic oil sprays.
im pretty sure it was earwigs, each destroyed cob i opened up had a bunch of them in there
An insecticidal soap solution like Safers (follow instructions on bottle) works really well on earwigs.
Earwigs are kind of a mixed bag. They can damage corn as well as other young plants, but they are also voracious consumers of mites, aphids and other soft bodied pests. They are also members of the decomposing community and play a valuable supporting role in helping dead organic matter get incorporated into the soil to benefit plants.
I have lots of earwigs around my property, but attribute very little in the way of plant damage to them.
They very well may have ruined your corn, but it is also quite possible they didn't move into the corn until some other pest damaged it in which case they found crawling inside to to be a comfy, moist, dark place to hang out and the decaying corn provided them a nearby food source.
Nevertheless if you believe you need to control their overall population then it helps to understand their life cycle.
Earwigs can be baited with vegetable oil that you place a tiny piece of bacon into. Set this inside tuna cans (or other shallow dish) and place in areas earwig presence is a concern. The earwigs will drown in the oil and this is non toxic to anything that doesn't drown in it. It is important to do this early on because overwintering earwigs promptly set about breeding and each female will lay around 30 eggs. So, each female you trap early on is 30 less earwigs in the garden later.
The use of an organic mulch favors earwigs. Organic mulches have so many benefits though that I would still advise using it. You can try raking the mulch a bit during the day when the earwigs are hiding to get them running for cover and being more vulnerable to predation, but don't expect great results from a raking or two. If birds are not a pest problem in your garden you can introduce cracked corn which attracts birds by the dozens. Birds are a natural enemy of earwigs. One warning though is cracked corn has a tendency to germinate, so some hoeing will be in order if you use it.
Lastly, earwigs need a moist hiding place during the day. I don't know how much rainfall you get or how you water the garden, but if you use drip irrigation or soaker hoses to limit the water to the crops instead of the entire mulched area this goes a long way to reducing the desirability of habitat for earwigs. If you gets lots of rainfall then this will be of limited effectiveness.
Other trapping methods that can be effective if started early in the season are rolling up a newspaper loosely and dampening it. Set it out at night and in the morning once the sun is out burn it or otherwise dispose of it so the earwigs in it can't get back to the garden. There will likely be scads of earwigs hiding out in it once the sun is up.
Before doing any of this though, make sure the earwigs really are the bad guys. They often get an undeserved bad rap when they are really just cleaning up the mess made by some other bug.
Alfalfa pellets also attract birds and don't sprout. Alfalfa pellets also make a great fertilizer so use them freely on a monthly basis.
Great post, very interesting.
I found that putting canola oil in empty cans attracts the earwigs and drowns them but was really uneffectively controlling their population. Also if you use sprinklers or if it rains around them it will overflow and leave marks on pavement and get into the soil which can kill certain plants (like my lawn).
Usually the cause of an infestation of earwigs is due to an inbalance in the garden system.
Try introducing chickens underneath trees where there is mulch buildup. Earwigs travel a fair distance at night time so introducing chickens into high mulch cool shaded areas is a good idea. You feed your chickens a controll the earwigs at the same time.
IF you dont have chickens get some!!! or cleanup the mulch around your yard an put it in one place for composting away from your corn and place canola oil traps. prehaps put some bird seed around the composting area to attract birds that will hopefully eat the earwigs.