THE popular Pest Bulletin organised by AHDB Horticulture is back for 2017, with new features and earlier forecasts.

Additions include using UK and overseas information to predict infestations of diamond-back moth (DBM) and silver Y moth more effectively.

It follows exceptionally high levels of DBM infestation in 2016 which hit cabbages.

The bulletin, hosted by Syngenta, gives forecasts and up-to-date reports for most key field crop pests.

The first immigrant DBMs of this season were found in mid-March, primarily in the South-west of England – arriving from the Continent with south-westerly winds.

Project lead, Dr Rosemary Collier, said: “It is probably too early for them to do major damage in the UK, but large migrations later in the year are likely to have an impact.”

"It is also possible that some diamond-back moths overwintered in the warmest parts of the country," she added.

For aphids, early forecasts from a Rothamsted survey suggested first flights by species such as myzus persicae will be about a week earlier than average.

Dr Collier said: “The general message from the Rothamsted survey is if spring doesn’t throw any wildly abnormal conditions at us, aphids will be flying a little earlier than usual, especially in the north and west.”

Cabbage root flies and carrot flies are already emerging towards the south of the UK and cabbage root flies are starting to lay eggs. Bean seed flies have also been on the wing for some time.

* To view the Pest Bulletin online, go to: www.syngenta.co.uk/ahdb-pest-bulletin. For observations and updates, head to blogs.warwick.ac.uk/rosemarycollier