Don’t skimp on slug control this autumn

Growers are being urged not to cut corners with slug control this autumn if populations are to be effectively controlled. 

With slug populations at heightened levels following the wet spring and summer, pellet choice and application timing could spell the difference between effective control and a decimated crop, warns De Sangosse.

“Growers are being bombarded with advice, not all of which is sound,” says Simon McMunn of manufacturer De Sangosse whose work suggests that one or two applications of a higher concentration, better quality pellet is preferable to repeated applications of a low rate pellet.

“Aside from the extra time and expense of multiple applications which distract from other operations there is also an increased vulnerability to the weather. All this suggests a quality pellet, such as TDS, if applied across one or two applications, rather than numerous applications of a lower concentration pellet, will achieve greater control,” says Simon McMunn.

Not all pellets are manufactured to the same standard so it is worthwhile stipulating the best quality wet process or the industry leading TDS pellet when ordering supplies, adds Mr McMunn.

“This will ensure you get a pellet that doesn’t breakdown quickly in the field,” he says.

The importance of the manufacturing process to pellet integrity and spreadibility should not be overlooked and he worries users might be misled into thinking that the higher number of baiting points achievable with lower concentration pellets is more important than using a quality pellet containing a slug attractant and that is capable of withstanding inclement conditions.

“Slug pellets are about the only pesticide in agriculture where we have to attract the pest to the chemical. There are several factors that influence the level of success, but they are all components of a quality pellet,” says Mr McMunn.

Factors that influence pellet efficacy
•    Pellet quality
•    Attractiveness
•    Persistence
•    Palatability
•    Spreadibility

Some commentators have been keen to promote the importance of baiting points, but Mr McMunn says much of this is overplayed.

“If baiting points are a concern, research shows that 30 pellets/m2 will deliver effective control, this is easily achievable with a TDS pellet and will ensure that the slug ingests sufficient bait for it to be fatal. But of greater importance to ensuring efficacy levels is pellet attractiveness,” he says.

“A TDS pellet will by design be slightly bigger than a lower concentration pellet. This will give it a greater density which will support its ballistic properties ensuring a more even and consistent spread while its lower surface area relative to the lower dose pellet means it will retain its integrity for longer in the field. This means the control period will be longer,” he adds.

Users of metaldehyde are required to observe the autumn restriction of 210g a.i./ha from 1st August to 31st December. 

One, well timed application of 5kg/ha of a TDS pellet during this period will deliver 200g metaldehyde per ha.