With soil moisture levels high this summer, arable growers must use good quality slug pellets, applied accurately, to control burgeoning slug populations. That is the advice from ADAMA’s molluscicides technical specialist, Andy Bailey, who also explains that spreading equipment must be properly calibrated to ensure accurate pellet application.
“The wet conditions throughout much of June and July have provided ideal conditions for an extended breeding window for slugs which means populations are already high, with reports of attacks on young oilseed rape crops coming in thick and fast,” Mr Bailey explains. “In those parts of the UK where the unsettled weather has continued into August, slug populations could be even greater, making it all the more vital for growers to apply a good quality slug bait on time and accurately.”
Molluscicides should only be used once populations have reached the appropriate damage-risk threshold per trapping point, and only if weather conditions are favourable.
Regular assessments to evaluate populations
“Applying slug pellets immediately prior to heavy rainfall can lead to their rapid degradation, especially if the pellets are of a poorer quality,” Mr Bailey continues. “Regular assessments to evaluate slug populations is the way to go, with spreading equipment calibrated and ready to be deployed as soon as the threshold point has been reached and a period of favourable, settled weather prevails.”
According to the National Sprayer Testing Scheme (NSTS), slug pellet applicators should be calibrated in accordance with the machinery manufacturer’s recommendations prior to and at regular intervals during the spreading season.
“Pellet spreaders and spinners should be positioned at an appropriate height for the machine on which they are mounted (typically 110cm above the ground for quad-mounted applicators) and operated at a sensible forward operating speed of around 12kph to ensure slug pellets are applied evenly and consistently over the entire spreading width,” Mr Bailey adds.
Pellet size and consistency are also vital to application accuracy. “The only molluscicide currently available in the UK is ferric phosphate,” Mr Bailey explains. “But, while there are many brands of pellet that use the same active ingredient, not all baits are created equally.
“Pellet size, weight and shape all have an effect on spreading ballistics, with only the best pellets able to achieve consistent and accurate spread patterns. Gusto IRON pellets, for example, are manufactured to strict tolerances to ensure they match their 2.5mm by 2.0mm size specification which ensures a consistent spread pattern and an optimal number of baiting points of 40-50 pellets per m2 when applied at typical field rates.”
Gusto IRON pellets also offer improved longevity in wet conditions and are characterised by their bright blue colour which makes them easily visible in seedbeds so that growers can quickly assess when a second application is required.
“Gusto IRON pellets contain 2.94% ferric phosphate which provides fast-acting protection against crop damage by suppressing slugs’ appetites as soon as they are ingested,” Mr Bailey describes. “The pellets also offer class-leading durability and palatability thanks to ADAMA’s ‘Desidro Technology’ manufacturing process which uses a two-stage drying process to ensure an ideal balance between pellet persistence and palatability, with Gusto IRON pellets proving hard enough to remain intact during wet weather whilst still remaining palatable and effective.”
The Desidro manufacturing process also gives Gusto IRON pellets excellent mould-resistance, with an independent trial showing that Gusto IRON pellets retain their shape, colour and palatability and remain mould-free for up to a week longer than other leading brands in wet conditions.
“Developing the perfect slug pellet takes a lot more research and development than many might imagine,” Mr Bailey concludes, “so it isn’t safe to assume that different brands will offer the same level of protection. It therefore pays to invest in good quality, long-lasting slug pellets such as Gusto IRON to keep valuable crops better protected for longer.”