At the bottom of this article you’ll see a photo of a slug trap one of my clients purchased a couple of years ago. As you can see, the trap consists of three wells that are designed to be filled with beer to lure in slugs and snails. A lid is placed on top of the box, presumably to make it dark and dingy (thus attractive to gastropods) and to stop any passing, thirsty birds getting drunk.
There are small entry points on each side and in theory and practice, the slugs and snails are attracted by the beer and crawl inside. They proceed to fall/slither into the wells and drown. If you’re someone selling or using the traps, you’ve probably convinced yourself they’re dying in beer-induced ecstasy but for the rest of us, they’re just drowning. Unfortunately, I’ve been responsible for emptying these traps and despite claims to the contrary, it seems all manner of other creatures including spiders, worms, woodlice and especially ground beetles are all partial to a bit of booze and get trapped just as often as slugs and snails.
The particularly observant among you will have noticed that despite the lack of beer in the traps in the photograph, they still have snails in them. I took this photo at the end of September when population numbers are on the wane but at the height of the summer, these traps will be packed full of slugs and snails even though there’s no beer inside, nor has there been for about 18 months. My theory is that the structure of the traps is enough to make the slugs and snails feel like they’re a good place to hang out. They’re often joined inside by frogs and toads who obviously agree. Better still, the underneath is ridged meaning that local newts, slugs and snails collect under there too.
So instead of throwing away a sludgy mess of beer and bloated bodies, I now go around and collect up all the slugs and snails and relocate them along the driveway, about 35 metres away from the vegetable garden where I found them. Slugs and snails have a homing instinct meaning they will try to find their way back to their original patch, but tests have found that taking them more than 20 metres away can overcome this homing tendency. This is not really a long-term solution for your whole garden but it works in areas where you have particularly vulnerable plants. And it’s definitely not an excuse to dump them in the garden of your annoying neighbour, but it might help reduce numbers around things such as seedlings or young dahlias. The long-term solution is to achieve a balanced plot where no one species proliferates, but that’s a topic for another post.
If you don’t already have some redundant beer traps hanging around, here’s a link to a handy guide to creating your own: www.slugwatch.co.uk I’d use a black plastic pot instead a clear one in order to create a gastropod-luring bunker. And remember, don’t waste good beer on drowning slugs. Good luck!