Recent rains have increased the risk of slug damage to rapeseed crops, so growers are urged to check crops and treat with granules where the pest is active and where the crop is vulnerable.
It’s been an exceptionally dry summer, and so far moisture-loving slugs aren’t on the list of potential threats that arable crop growers need to worry about.
However, Eric Anderson of Scottish Agronomy says recent rains – heavy and heavy in some areas – have wetted soils again, almost to the point where they are no longer needed.
Where rapeseed has been sown, crops have been relatively slow to start and remain vulnerable to slug attack at a time when the onset of humidity sees their numbers increase.
Mr Anderson says crops need to be carefully monitored for any signs of damage and bait traps can also provide a useful indicator of risk.
“When problems are identified, granules should be applied. The preferred option would be 5 kg/ha of Sluxx HP, as its granule integrity is better than other ferric phosphate granules on the market.
“If the wet weather and threat persists and the crop is still vulnerable, repeat treatments should be applied every seven days until the rapeseed plants reach the three true leaf stage,” he explains. .
Growers have been busy planting barley and winter wheat at the start of winter after a relatively easy harvest in northern Britain and increased soil moisture is also increasing the slug activity in these crops.
“Particularly in the early wheats after rapeseed, where the risk is most acute, the control strategy should be the same for rapeseed,” says Anderson.
He adds that sowing conditions have been good so far, but with much wetter soil than before, producing a fine, well-consolidated seedbed could prove more difficult and further increase the risk of slugs in the coming weeks.