By Dr Andy Evans of SRUC,

for the Farm Advisory Service

The pressure on pesticides is higher than ever, with a new report on the dangers of glyphosate and headlines such as ‘Plummeting insect numbers threaten collapse of nature’ in the broadsheets.

And so, we continue to lose pesticides. The news just before Christmas that metaldehyde slug pellets will disappear from June, 2020, came as a surprise. We now have 14 months or so to use up stocks before metaldehyde can no longer be used.

It is still essential that unnecessary use of metaldehyde pellets is avoided in order to reduce the risk of detection in water, so the metaldehyde stewardship guidelines, including the recommendation that no metaldehyde pellets should be allowed to fall within a minimum of 10m of any field boundary or watercourse, still need to be adhered to.

Ferric phosphate pellets are a good alternative to metaldehyde and are as effective at managing slugs, so when metaldehyde goes in 2020, we will still have an option for effective slug management.

As the temperatures are starting to warm up, slugs are starting to feed and backward crops of wheat, in particular, could be at risk. Growers need to plan their potential slug pellet usage for the whole calendar year, making sure that options are considered for use on summer crops (eg potatoes, field vegetables) and the subsequent autumn crop (eg wheat, oilseed rape) that keep metaldehyde use within the annual recommended limits of 700g of active ingredients per year and 210g from August 1 to December 31.

With spring barley sowing approaching, crops to be sown after grass may be at risk f

rom leatherjackets. With the loss of chlorpyrifos, there are now no insecticide treatments available for leatherjacket management.

If possible, plough in the grass ley now and delay sowing the spring crop for as long as possible. Leatherjackets will start feeding voraciously in March and die because of lack of food. The act of ploughing and winter kill will hopefully knock back leatherjacket populations to less damaging levels.

Rolling the seedbed with a heavy roller immediately after sowing can also reduce damage by leatherjackets.