Check or aphids on emerging shoots as they could be walking onto the crop from volunteers and grasses, and some aphids have already been flying around this spring. An aphicide should be considered if aphid colonies are found as they could be carrying barley yellow dwarf virus (BYDV) and potentially spreading it into the crop.
Crops sown after grass will be at risk from leatherjackets. With 6 out of 10 fields sampled in our leatherjacket survey having leatherjacket counts above the 0.6 million grubs/ha threshold likely to cause damage to the following spring crop such as spring barley, there is a risk this season. Rolling the seedbed with a heavy roller immediately after sowing can also reduce damage by leatherjackets.
Check for signs of leaf shredding by slugs at early crop emergence. Bear in mind that if you are to use slug pellets that there are guidelines as to how much metaldehyde pellets you can apply and that no metaldehyde pellets should be allowed to fall within a minimum of 10 metres of any field boundary or watercourse. A maximum of 700g metaldehyde a.i. is allowed in a calendar year, with a maximum of 210g after August. Ferric phosphate products are good alternatives to metaldehyde. Note that you will not be able to purchase any metaldehyde product after 30th June, and all stocks will need to be used by 30th June 2020.
Other pests such as rabbits and wireworm can all have an impact on crop establishment. Make sure that the cause of any poor growth is determined as options for management of the above will vary.
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