'Slug sleuth' farmers cut pesticide use in half with a homemade map

A new mapping tool pinpoints where the molluscs are most likely to strike, helping farmers cut pesticide use while protecting precious crops

A new mapping tool pinpoints where the molluscs are most likely to strike, helping farmers cut pesticide use while protecting precious crops

Slugs are the slimy bane of many a farmer’s life, but their days of munching on precious crops could be numbered thanks to a new tool that predicts where the pests will strike.

It’s the result of groundbreaking research from a consortium led by the British On-Farm Innovation Network (BOFIN).

One strand of the three-year, £2.6m project – funded by Defra – employed a network of ‘slug sleuth’ farmers working as field researchers to suss out the molluscs’ favoured soil types.

The monitoring has led to the development of a digital field mapping tool , which pinpoints vulnerable slug hotspots, meaning farmers can deploy pesticides with new precision instead of randomly treating entire fields.

Growers taking part in a pilot were able to slash the use of slug pellets by an average of 50% as a result. Widescale adoption across the UK’s arable industry could save farmers £6m a year, researchers estimate.

BOFIN founder Tom Allen-Stevens said the new innovation was not the project’s only major breakthrough. “No one has used farmers to gather scientific evidence like this before, so one of our biggest findings is that farmers can do research,” he said. “Farmers deserve more respect for their intelligence: no one knows the land better.”

Slugs pose a £44m-a-year headache for farmers growing crops such as wheat and oilseed rape. As well as grazing on shoots, they munch the seeds of barley, oat and wheat, and can devastate entire fields of vegetables.

Ferric phosphate pellets are the main line of defence, but they are a more expensive treatment than the now-banned chemical metaldehyde.

In search of a solution, BOFIN’s playfully titled ‘Slimers’ project (‘Strategies leading to improved management and enhanced resilience to slugs’) recruited 28 farmers to monitor where the pests gathered in their fields by setting traps.

The data, alongside soil sampling, informed a computer model, which farmers can now access for free to produce their own ‘slug risk’ map. That in turn can be plugged into an automated pellet applicator that drops the pesticide only where it’s needed.