TheSay NO to DRIFT stewardship initiative is warning growers to be aware thatthere is an increased threat to grass leys, following a bumper year for the leatherjacketpest in 2013.
Leatherjacket grubsare larger than usual for the time of year, so farmers need to be alert for anydamage; particularly on establishing grass leys where they are following grass,but also to late drilled and spring cereal crops, comments Brent Gibbon of DowAgroSciences. Hatched leatherjackets are vulnerable to desiccation,particularly when young, however the wet winter will have kept the soil moistand aided their survival.
The stewardship initiative isurging growers to monitor fields known to have a history of leatherjacketdamage, Look out for large numbers of rooks and jackdaws feeding on thelarvae, notes Brent. Cereals following established grass leys, a grassystubble or spring barley are high risk crops. Permanent grassland and newlysown leys are also more likely to suffer yield damages from this pest, sogrowers need to be aware, warns Brent.
Chlorpyrifosis an effective insecticide, which following months of feeding by the pest canhelp prevent further damage, thus protecting the yield. It is vital thatfarmers firstly, have a strong knowledge of their lands pest and diseasehistory, and secondly look for indicators of leatherjackets in their crops,before treating.
Inrecently planted crops, checking the top soil gives a good idea of pestactivity; using a trowel, lift a few clods of soil working across the fields, acouple of inches deep to see if there are any grubs. Once the crops startgerminating look for signs of damage around the base of the plant and the root.Be sure to treat at the first sign of activity, advises Brent.
When applying chlorpyrifos for treatment ofleatherjackets, growers should use LERAP rated 3 star nozzles and adopt a 20metre no-spray buffer zone near to watercourses or a 1 metre near to dryditches. It is vital that growers adopt the stewardship guidelines whenapplying chlorpyrifos in order to help secure a future for this keyinsecticide, concludes James.
For full details of the Say NO to DRIFTstewardship guidelines, please visit www.saynotodrift.co.uk/arable/