Latin name: Brassica napus
Plant description: Oil seed rape is a crop grown for vegetable oil.
The bright yellow fields with their distinctive scent have become
a familiar site in the UK countryside.
Distribution: UK: arable areas, especially the south, Midlands, East Anglia and some parts of Northern England and southern Scotland. Also across much of Europe to the Mediterranean.
Allergenicity and other health impacts: The crops are often blamed for triggering symptoms of hay fever although only around 1 in 25 sufferers of seasonal allergies test positive to oil-seed rape allergen. In addition, the flowers are insect-pollinated and only low to moderate amounts are caught on the wind and dispersed away from the crop. The oil-seed rape flowering season coincides with those of the more highly allergenic birch and oak pollen seasons which are far more likely to cause symptoms. However, the crops do give off volatile organic compounds which can cause irritation of the upper respiratory system, giving a range of symptoms from irritated eyes to coughs and even bronchial conditions in some people.
Season: Late March to early July, usually peaking in April or early May.