Pollen Beetle Forecast

Background

Adult pollen beetles (Brassicogethes spp.) are occasional pests of cauliflower and broccoli. The adult beetles feed on the curds or florets causing physical damage. This type of damage usually occurs in mid-summer when new adults emerge from oil seed rape crops and move into other areas to feed. They are also often found in flowers at this time. These new adults feed for a period of time and then seek hibernation sites, for example in leaf litter at the base of hedges. They overwinter as adults and emerge from hibernation in spring, when they can again be seen feeding on flowers such as dandelions. They then move to suitable host plants such as oil seed rape to lay eggs. Once hatched, the larvae feed on flower buds and then drop to the soil to pupate, from which the new generation of adults emerges.

Location	Estimated start of pollen beetle migration into edible brassica crops
Cornwall - Hayle	24 Jun
Kent - Sandwich	15 Jun
Suffolk - Ipswich	18 Jun
Warwick, Wellesbourne	20 Jun
Norfolk, Norwich	30 Jun
Lincolnshire - Holbeach	25 Jun
Nottingham - Stubton	22 Jun
Lancashire, Southport	1 Jul
Yorkshire, York	27 Jun
Perthshire, Scotland	10 Jul