Winter Oilseed Rape Fact Sheet (81KB, PDF Format)
Oilseed rape is a member of the Bracassia family and is grown for its oil content.
There are a number of types of oilseed rape (either winter or spring ) which can be grown.
Oilseed rape can be further segregated into “Double low” varieties, HEAR varieties and HO, LL varieties . Oilseed rape naturally produces contain some unwanted compounds; erucic acid and glucosinolates. These compounds were found to be harmful (immunotoxic) to both humans and animals.
'Double low' varieties (low erucic acid, less than 2% of measured fatty acid, and low glucosinolates, less than 35mmol/kg in the meal) are the most commonly grown in Ireland and typically have oil content of 43-44%.
HEAR (high erucic acid rape) varieties are more specialised and are generally grown for specialist markets (including bio-fuels) and are regarded as non-food crops.
HO, LL (high oleic, low linolenic fatty acid profile) varieties are healthier for human consumption and have high stable oil for the food processing industry.
The popularity of oilseed rape has increased over the past few years due to the dramatic increase in price and also because growers are looking for alternative crops to cereals. There are two sowing times for rape in Ireland; Winter oilseed rape and Spring oilseed rape. The overall acreage of winter oilseed is around 8,000 hectares and increasing and spring oilseed rape acreage is around 4,000 hectares. Yield of winter and spring oilseed rape are very different. Average yields of winter oilseed rape in Ireland are 4.2 tonnes per hectare, with highs of 5.0 tonnes per hectare achieved in 2011. Spring oilseed rape average yields are 2.2 tonnes per hectare with highs of 3.3 tonnes per hectare harvested in 2010.
Oilseed rape acts as a break crop from the Take-all fungus which adversely affects wheat. Yield of wheat sown after sowing rape can increase by 0.5-1.5 t/ha depending on the incidence of take all during the growing season.
Oilseed Rape Key Statistics
Data from Teagasc Harvest Reports 2008-2012