Slugs could leave a sour taste for sugar beet growers
With already high slug populations as sugar beet drilling starts, growers are being urged to monitor the pest during the early stages of crop growth.
That is the advice from Bayer’s molluscicide manager, Peter Stacey, who believes the recent cold spell will have had little negative effect on slug numbers.
“Populations built up through 2012 and they could cause sugar beet growers many more problems than in previous years,” he adds.
Sugar beet crops that could be considered “high risk” are those that have been established after autumn and/or over-winter cover crops or ground cover.
The usual rules apply for seed-bed preparation, with a fine and well consolidated soil being the first step in reducing the risk from this potentially damaging pest.
Following this, the crop is most vulnerable to slug attack between emergence and the 2-4 true leaf stages, so that is the time growers need to place traps and monitor numbers.
Mr Stacey points out that crops sitting in cold and wet soils may be more at risk as they will struggle to grow rapidly away from damage susceptible growth stages.
Once the crop has reached the four true leaf stage, any damage caused by the slugs is of less economic consequence and will rarely justify treatment.
Growers should check fields prior to drilling using shelter traps – baited with layer’s mash – and use them throughout crop emergence, advises Mr Stacey.
“If slugs are found in any of the traps then a treatment with slug pellets will be necessary,” he adds.
Independent sugar beet agronomist Pat Turnbull also reminds growers of the value of regularly walking crops to ensure any feeding is picked up early.
“Slugs can feed above and below ground, so it’s a case of getting in the crop and looking closely for signs of damage,” she says.
Dr Turnbull is also hopeful that if there is some rapid drying during April, slugs may retreat deeper into the soil profile and not be a problem.
Pellet choice
When treating for slugs there are three active ingredient options for pellets, which include metaldehyde, ferric phosphate and methiocarb.
Dr Turnbull believes that metaldehyde will remain the number one choice, but reminds growers to keep within the metaldehyde stewardship limits.
“I also have growers that are successfully using ferric phosphate pellets, but whatever the choice, good pellet quality is essential,” she adds.
She advises to go for a wet processed pellet to ensure durability, with the open nature of the sugar beet crop in its early stages leaving any pellets exposed to the elements.
Methiocarb is also an option, she continues, but there is an associated higher cost when compared with the other pellets on the market.
