Following a short break during the cold snap, this week’s Dow AgroSciences Pestwatch report shows that Wheat Bulb fly egg-hatch has now started in Yorkshire, is imminent in Scotland and is progressing Suffolk and Lincolnshire. Plant invasion is progressing albeit slowly at the Suffolk, Cambridgeshire and Lincolnshire.
Issued weekly by Dow AgroSciences and ADAS, Pestwatch reports on the results of soil sampling at a number of sites across the UK and provide advice on the timely application of the soil insecticide Dursban WG. Weekly information can be accessed at http://www.dowagro.com/uk/cereal/pest.htm. Week-ending the 24th February 2012, Wheat Bulb fly egg-hatch in Suffolk was reported to be 66.7%, in Cambridgeshire/Hertfordshire on mineral soils was 26.1%, North Lincolnshire (a new site for 2012) on mineral soils 23.1%, Yorkshire on mineral soils at 5% and in Cambridgeshire on organic land was 27.5%.
Sarah Hurry of Dow AgroSciences explains that fields at risk, particularly in East Anglia and Lincolnshire, need Dursban WG (chlorpyrifos) at the first opportunity as tiller survival is important. “This application should be active for 5 to 6 weeks on mineral soils. Dursban WG can be applied to frosty ground, but should not be tank-mixed.â€
If applying Dursban WG growers should be aware of an interval of 14 days between applications of Dursban WG and GF-2070 or Broadway Star, regardless of weather conditions. For approved formulations of iodosulfuron-methyl-sodium and mesosulfuron-methyl, a longer interval of 4 weeks is required for crop safety reasons.
When applying Dursban WG for Wheat Bulb fly, growers are advised to use low drift nozzles and extend buffer zones. They should use LERAP rated 3 star nozzles and adopt a 20 metre no-spray buffer zone near to watercourses or a 1 metre near to dry ditches. This advice is part of a new Stewardship ‘Say NO to drift’ initiative which aims to support the future availability and use of insecticides containing chlorpyrifos.
Growers and advisors can go to www.saynotodrift.co.uk where they can see can see video of spraying with low drift nozzles versus conventional flat-fan nozzles plus other details of good Stewardship.
