Not that I know of but found this on a site (copyright acknowledged) Q Can you suggest the best way of dealing with earwigs which are devouring my dahlias, clematis and chrysanthemums? A The best way of controlling earwigs is to set a straw trap for them. Place bamboo canes among your plants and then place an upturned pot full of straw on top of each one so that the pot is level with the flowers; the earwigs will hide in the straw. Check the pots daily and dispose of any earwigs you find. Also make sure that any debris surrounding the plants is cleared up regularly as this material provides perfect hiding places for the earwigs. You can also smear a layer of petroleum jelly on the flower stems of your plants. This acts as a barrier which the earwigs won't cross and so protects the blooms from damage.
Bio control is a bit of a pet interest of mine, not so much in localised situations, but in large scale pest eradication. This link gives some info on bio control plans for Japanese Knotweed, and a pretty good overview of how it works generally: Japanese Knotweed Alliance My only concern is that in spite of their positive approach, you can never be sure that the predator won't turn on another species once it has done the job that it is meant to - or conversely that it will become the target of another natural predator which was previously saving us from being overrun by something else. I don't believe you can thoroughly replicate the diversity of the natural world through laboritory testing, and there have been some notable mistakes with bio control in the past. The comment that scientists spend "considerable time (at least 3 years)" assessing the potential impact is especially interesting. I'm not advocating the use of chemicals over bio control, but most chemicals spend about 12 years in testing before they can be licensed, and yet they are often found to be damaging after several years in their intended environment. It's a very interesting subject though, and despite the few mistakes that have been made, it seems to be largely successful.
