Conditionsover the last week have generally not been suitable for pollen beetle migration, says Bayer CropScience.
Only three more met stations have turned red on the migration start map.Ashford and Faversham inKent turned red last Tuesday 17th March and on Friday 20thMarch Perth turned red making it the first of Scotlands seven met stations todo so.
Although thepollen beetle season has begun across half the country migration is proceedingvery slowly due to the prevailing cool conditions. On the percent migrationmap, met stations where migration has already begun are only showing from fourto 10 percent migration complete. So the national outlook is that crops stillface 90 to 100 percent of pollen beetle migration yet to come.
Bayers Agri Servicesmanager Nathan Whitehouse says: Take this opportunity to count plant numbersin readiness to apply the new thresholds. Its much easier to assess plantpopulations when crops are short. You can approximate the number of plants persquare metre by counting the number of plants per square foot and multiplyingby 11. This should be near enough to place a crop in one of the four thresholdbands.
Growers whoincreased seed rate and sowed earlier last autumn to pre-empt the threat ofcabbge stem flea beetle may well have pretty thick crops by now. Its importantto gauge plant population because the thicker the crop the lower the thresholdfor pollen beetle damage and vice versa.
Access pollenbeetle predictor at: www.bayercropscience.co.uk/pollenbeetlepredictor