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19th February 2020
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Slug trouble

Posted 12/05/2015 by sevans

The sun is out, Spring is in the air and already the lovingly nurtured seedlings in my garden have taken a hammering from a veritable army of slugs.

Britain, according to an article I found on the web, is the ‘slug capital of the world’. Apparently there are more than 30 different species, of which four - the Field Slug. The Garden Slug, The Keel Slug and the Black Slug - are the most damaging in our gardens, notes Professor William O. C. Symondson, a world authority on the subject at Cardiff School of Biosciences, and whose article also cites among its sources A field guide to the slugs of the British Isles.

Yet the perennial problem for gardeners, of course, is not how to identify slugs but what to do to get rid of them – ideally without harming the rest of the friendlier bugs and wildlife camped out in the veg patch. By far the favourite choice – and probably the most common pesticide used in gardens and allotments up and down the country – are the familiar blue slug pellets containing the chemical metaldehyde (CH3CHO)4). Cheap and effective, however, wildlife friendly such pellets are not, blamed for large numbers of accidental poisonings of children and pets, not to mention of birds and other untargeted species.

Browsing through the shelves of my local B&Q, this week, I was delighted therefore to discover a whole cornucopia of products claimed as kinder to the environment – from traps and baits to pricier mail order nematodes (although, since these promise longer term removal, maybe the price is reasonable). In the end, I settled on a two-pronged approach: a tube of organic Advanced Slug Killer pellets based on ferric phosphate which, it is claimed, will be broken down by microorganisms to iron and phosphate in the soil. Also found in some fertilisers, ferric phosphate is poisonous to slugs and snails but promises to be relatively harmless for most other wildlife, including humans.

Sadly, however, it’s not just the slug pellets that are a problem in our gardens. As the shelves of any local garden centre testify, there is now a bamboozling array of products on offer for anything from aphid and weed control to lawn improver and patio and mould cleaners – nearly all of them containing ‘hazardous chemicals’ of one type or another. Used in the wrong dosages, in inexperienced or careless hands, such ingredients have the potential to wreak havoc on our natural surroundings.

Carefully tended gardens are a much needed haven for our already threatened wildlife. But they rely on thoughtful and assiduous gardeners cultivating an environment to support our birds, bugs and bees - not merely adopting lazy solutions for creating perfectly manicured lawns.

Cath O’Driscoll - Deputy editor

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